Optical-Scanning-Height Measuring Device

ABSTRACT

To provide an optical-scanning-height measuring device capable of reducing an unmeasurable region on the surface of a measurement object. Light emitted from a light emitting section is deflected by a deflecting section according to designation of a measurement point. Measurement light is sequentially irradiated on a plurality of portions P in a partial region PA including or surrounding a part of a measurement object S corresponding to the measurement point. A deflecting direction of the deflecting section corresponding to the partial region PA or an irradiation position of the measurement light corresponding to the partial region PA are detected by a detecting section.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims foreign priority based on Japanese PatentApplication No. 2016-256614, filed Dec. 28, 2016, the contents of whichis incorporated herein by reference.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to an optical-scanning-height measuringdevice that measures a surface shape of a measurement object.

2. Description of Related Art

An optical-scanning-height measuring device is used to measure a surfaceshape of a measurement object For example, in a dimension measuringdevice described in JP-A-2010-43954, light irradiated from a white lightsource is divided into a measurement light beam and a reference lightbeam by an optical coupler. The measurement light beam is scanned by ameasurement-object scanning optical system and irradiated on anymeasurement point on the surface of a measurement object. The referencelight beam is irradiated on a reference-light scanning optical system. Asurface height of the measurement point of the measurement object iscalculated on the basis of interference of the measurement light beamand the reference light beam reflected by the measurement object.

SUMMARY OF THE INVENTION

As explained above, in the dimension measuring device described inJP-A-2010-43954, in order to calculate surface height of a measurementpoint, the measurement light beam reflected by the measurement object isused. However, depending on a direction of the measurement light beamirradiated on the measurement point by the measurement object scanningoptical system and a surface state of the measurement object at themeasurement point, the measurement light beam reflected from themeasurement object sometimes cannot be obtained at sufficient strengthnecessary for the measurement. In this case, an unmeasurable regionappears on the surface of the measurement object.

An object of the present invention is to provide anoptical-scanning-height measuring device capable of reducing anunmeasurable region on the surface of a measurement object.

(1) An optical-scanning-height measuring device according to the presentinvention includes: a position-information acquiring section configuredto receive designation of a measurement point; a light emitting sectionconfigured to emit light; a deflecting and irradiating sectionconfigured to deflect the light emitted from the light emitting sectionand irradiating the light on a measurement object to sequentiallyirradiate the light on a plurality of portions different from oneanother in a partial region on a surface of the measurement objectincluding or surrounding a portion of the measurement objectcorresponding to the measurement point received by theposition-information acquiring section; a light receiving sectionconfigured to receive light from the measurement object and output alight reception signal indicating a received light amount; a detectingsection configured to detect a deflecting direction of the deflectingand irradiating section corresponding to the partial region or anirradiation position of the measurement light corresponding to thepartial region; and a height calculating section configured tocalculate, on the basis of the deflecting direction of the deflectingand irradiating section or the irradiation position of the measurementlight detected by the detecting section and the light reception signaloutput from the light receiving section according to incidence of lightson the light receiving section from the plurality of portions in thepartial region, height of the portion of the measurement objectcorresponding to the designated measurement point.

In the optical-scanning-height measuring device, the designation of themeasurement point is received by the position-information acquiringsection. The light emitted from the light emitting section is deflectedby the deflecting and irradiating section. Consequently, the light issequentially irradiated on the plurality of portions in the partialregion on the surface of the measurement object. At this point, thedeflecting direction of the deflecting and irradiating sectioncorresponding to the partial region or the irradiation position of themeasurement light corresponding to the partial region is detected by thedetecting section.

The light from the measurement object is received by the light receivingsection and the light reception signal indicating the received lightamount is output. The height of the portion of the measurement objectcorresponding to the measurement point is calculated by the heightcalculating section on the basis of the deflecting direction of thedeflecting and emitting section or the irradiation position of themeasurement light detected by the detecting section and the lightreception signal output from the light receiving section according tothe incidence of the lights on the light receiving section from theplurality of portions in the partial region.

With this configuration, the light emitted from the light emittingsection and deflected by the deflecting and irradiating section isirradiated on the plurality of portions in the partial region of themeasurement object. Consequently, the light is reflected to the lightreceiving section from at least a part of the plurality of portions,whereby, irrespective of a direction of the light and a surface state ofthe measurement object, it is possible to acquire, at sufficientstrength, the light reception signal output from the light receivingsection. Therefore, it is possible to calculate, on the basis of theacquired light reception signal, the height of the portion of themeasurement object corresponding to the measurement point. As a result,it is possible to reduce an unmeasurable region on the surface of themeasurement object.

(2) The deflecting and irradiating section may include: a deflectingsection configured to deflect the light emitted from the light emittingsection and irradiate the light on the measurement object; and a drivingcontrol section configured to control the deflecting section tosequentially irradiate the light on the plurality of portions in thepartial region corresponding to the measurement point received by theposition-information acquiring section.

In this case, a component that guides the light to the plurality ofportions in the partial region is unnecessary other than the deflectingsection. Therefore, the configuration of the optical-canning-heightmeasuring device is simplified.

(3) The deflecting and irradiating section may include: a deflectingsection configured to deflect the light emitted from the light emittingsection and irradiating the light on the measurement object; a shiftsection provided between the light emitting section and the deflectingsection and configured to shift a traveling direction of the lightemitted from the light emitting section to a direction orthogonal to thetraveling direction; and a driving control section configured to controlthe deflecting section and the shift section to sequentially irradiatethe light on the plurality of portions in the partial regioncorresponding to the measurement point received by theposition-information acquiring section.

In this case, the traveling direction of the light guided from the lightemitting section to the deflecting section is shifted by the shiftsection, whereby the light is sequentially irradiated on the pluralityof portions in the partial region. Therefore, when a configurationincluding the deflecting section is existing, it is possible to easilyreduce the unmeasurable region in the measurement object by providingthe shift section in the configuration.

(4) The partial region may be an annular region surrounding thedesignated measurement point, and the plurality of portions of thepartial region may be arranged in a circumferential direction of theannular region.

In this case, it is possible to smoothly irradiate the light on theplurality of portions in the partial region by scanning the light in thecircumferential direction on the annular region.

(5) When the position-information acquiring section sequentiallyreceives designation of first and second measurement points, after theposition-information acquiring section receives designation of the firstmeasurement point and before the position-information acquiring sectionreceives designation of the second measurement point, the deflecting andirradiating section may be capable of deflecting the light emitting fromthe light emitting section and irradiating the light on the measurementobject to sequentially irradiate the light on a plurality of portions ina partial region on the surface of the measurement object including orsurrounding a portion of the measurement object corresponding to thedesignated first measurement point.

In this case, the height of the portion of the measurement objectcorresponding to the measurement point is calculated every time theposition-information acquiring section receives the measurement point.The calculation of the height is executable before theposition-information acquiring section receives designation of the nextmeasurement point. Consequently, it is possible to quickly measureheights of a plurality of portions of the measurement object.

(6) The optical-scanning-height measuring device may further include: aplacement table on which the measurement object is placed; a headsection including the light emitting section, the deflecting andirradiating section, and the light receiving section; and a holdingsection configured to integrally hold the head section and the placementtable to irradiate, on a placement surface of the placement table fromabove, the light emitted from the light emitting section and deflectedby the deflecting and irradiating section.

In this case, the head section and the placement table are integrallyheld by the holding section. Consequently, it is easy to handle theoptical-scanning-height measuring device compared with when the headsection and the placement table are respectively provided as separatebodies. It is unnecessary to separately prepare a fixture for fixing thehead section.

(7) The holding section may be capable of moving the head section in adirection orthogonal to the placement surface of the placement table.Consequently, it is possible to easily change the distance between themeasurement object placed on the placement surface and the head section.

(8) The optical-scanning-height measuring device may further include animaging section provided in the head section and configured to image themeasurement object placed on the placement table, and theposition-information acquiring section may receive designation of ameasurement point on an image of the measurement object acquired by theimaging section.

In this case, a user can easily designate the measurement point on theimage of the measurement object acquired by the imaging section.

(9) The optical-scanning-height measuring device may further include: areference body disposed to be movable on a movement axis; a light guidesection configured to guide the light emitted by the light emittingsection to the deflecting and irradiating section as measurement lightand guide the light emitted by the light emitting section to thereference body as reference light, generate interference light of themeasurement light from the measurement object reflected by thedeflecting and irradiating section and the reference light reflected bythe reference body, and guide the generated interference light to thelight receiving section; a reference-position acquiring sectionconfigured to acquire a position of the reference body; and a spectralsection configured to spectrally disperse the interference lightgenerated by the light guide section. The light emitting section mayemit temporally low-coherent light. The deflecting and irradiatingsection may deflect the measurement light guided by the light guidesection to irradiate the measurement light on the plurality of portionsin the partial region and reflect the measurement light from themeasurement object to the light guide section. The light receivingsection may receive the interference light spectrally dispersed by thespectral section and output a light reception signal indicating areceived light amount for each of wavelengths of the interference light.The height calculating section may calculate height of the portion ofthe measurement object on the basis of the position of the referencebody acquired by the reference-position acquiring section and thereceived light amount for each of the wavelengths of the interferencelight in the light reception signal output from the light receivingsection.

In this case, it is possible to highly accurately calculate the heightof the portion of the measurement object corresponding to the designatedmeasurement point on the basis of the position of the reference bodythat reflects the reference light and the received light amount for eachof the wavelengths of the spectrally dispersed interference light

(10) The optical-scanning-height measuring device may be configured toselectively operate in a setting mode and a measurement mode and furtherinclude a registering section. The position-information acquiringsection may receive, in the setting mode, the measurement point on animage of a first measurement object. The registering section mayregister, in the setting mode, the measurement point received by theposition-information acquiring section. The deflecting and irradiatingsection may deflect, in the measurement mode, the light emitted from thelight emitting section and irradiate the light on the measurement objectto sequentially irradiate the light on a plurality of portions differentfrom one another in a partial region on a surface of a secondmeasurement object including or surrounding a portion of the secondmeasurement object corresponding to the measurement point registered bythe registering section. The detecting section may detect, in themeasurement mode, a deflecting direction of the deflecting andirradiating section or an irradiation position of the measurement lightcorresponding to the partial region. The height calculating section maycalculate, in the measurement mode, height of the portion of the secondmeasurement object corresponding to the measurement point.

In this case, in the setting mode, the measurement point on the image ofthe first measurement object is registered by the registering section.In the measurement mode, the height of the portion of the secondmeasurement object corresponding to the registered measurement point isautomatically calculated. Therefore, a skilled operator designates themeasurement points on the image of the first measurement object in thesetting mode, whereby, in the measurement mode, even when the operatoris not skilled, it is possible to uniformly acquire a calculation resultof the height of the corresponding portion of the second measurementobject. Consequently, it is possible to accurately and easily measurethe shape of a desired portion of the measurement object.

According to the present invention, it is possible to reduce theunmeasurable region on the surface of the measurement object.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram showing an overall configuration of anoptical-scanning-height measuring device according to an embodiment ofthe present invention.

FIG. 2 is an exterior perspective view showing a stand section shown inFIG. 1.

FIG. 3 is a block diagram showing the configurations of the standsection and a measurement head.

FIG. 4 is a schematic diagram showing the configuration of a measuringsection.

FIG. 5 is a schematic diagram showing the configuration of a referencesection.

FIG. 6 is a schematic diagram showing the configuration of a focusingsection.

FIG. 7 is a schematic diagram showing the configuration of a scanningsection.

FIG. 8 is an enlarged perspective view schematically showing a state inwhich measurement light is irradiated on a specified position on thesurface of a measurement object.

FIGS. 9A to 9C are schematic diagrams showing other examples of apartial region.

FIG. 10 is a diagram showing an example of a selection screen displayedon a display section of the optical-scanning-height measuring device.

FIGS. 11A to 11C are diagrams showing contents of data transmittedbetween a control section and a control board in operation modes.

FIG. 12 is a block diagram showing a control system of theoptical-scanning-height measuring device shown in FIG. 1.

FIG. 13 is a diagram showing an example of a report prepared by a reportpreparing section.

FIG. 14 is a flowchart for explaining the example of the opticalscanning height measurement processing executed in theoptical-scanning-height measuring device shown in FIG. 1.

FIG. 15 is a flowchart for explaining the example of the opticalscanning height measurement processing executed in theoptical-scanning-height measuring device shown in FIG. 1.

FIG. 16 is a flowchart for explaining an example of optical scanningheight measurement processing executed in the optical-scanning-heightmeasuring device shown in FIG. 1.

FIG. 17 is a flowchart for explaining the example of the opticalscanning height measurement processing executed in theoptical-scanning-height measuring device shown in FIG. 1.

FIG. 18 is a flowchart for explaining an example of designation andmeasurement processing by the control board.

FIG. 19 is a flowchart for explaining an example of designation andmeasurement processing by the control board.

FIGS. 20A to 20C are explanatory diagrams for explaining the designationand measurement processing shown in FIGS. 18 and 19.

FIGS. 21A and 21B are explanatory diagrams for explaining thedesignation and measurement processing shown in FIGS. 18 and 19.

FIG. 22 is a flowchart for explaining another example of the designationand measurement processing by the control board.

FIG. 23 is a flowchart for explaining the other example of thedesignation and measurement processing by the control board.

FIGS. 24A and 24B are explanatory diagrams for explaining thedesignation and measurement processing shown in FIGS. 22 and 23.

FIG. 25 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 26 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 27 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 28 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 29 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 30 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 31 is a diagram for explaining the other operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 32 is a diagram for explaining the other operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 33 is a diagram for explaining the other operation example of theoptical-scanning-height measuring device in the setting mode.

FIG. 34 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the measurement mode.

FIG. 35 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the measurement mode.

FIG. 36 is a diagram for explaining the operation example of theoptical-scanning-height measuring device in the measurement mode.

FIG. 37 is a schematic diagram showing another configuration example ofthe reference section.

FIG. 38 is a block diagram showing another configuration example of thecontrol system of the optical-scanning-height measuring device.

FIG. 39 is a schematic diagram showing another configuration example ofthe optical section of the optical-scanning-height measuring device.

DESCRIPTION OF EMBODIMENTS (1) Overall Configuration of anOptical-Scanning-Height Measuring Device

An optical-scanning-height measuring device according to an embodimentof the present invention is explained below with reference to thedrawings. FIG. 1 is a block diagram showing an overall configuration ofthe optical-scanning-height measuring device according to the embodimentof the present invention. FIG. 2 is an exterior perspective view showinga stand section 100 shown in FIG. 1. As shown in FIG. 1, anoptical-scanning-height measuring device 400 includes the stand section100, a measurement head 200, and a processing device 300.

The stand section 100 has an L shape in longitudinal cross section andincludes a setting section 110, a holding section 120, and a lift 130.The setting section 110 has a horizontal flat shape and is set on asetting surface. As shown in FIG. 2, a square optical surface plate 111on which a measurement object S (FIG. 1) is placed is provided on theupper surface of the setting section 110. A measurement region V wherethe measurement object S can be measured by the measurement head 200 isdefined above the optical surface plate 111. In FIG. 2, the measurementregion V is indicated by a dotted line.

In the optical surface plate 111, a plurality of screw holes are formedto be arranged at equal intervals in two directions orthogonal to eachother. Consequently, it is possible to fix the measurement object S tothe optical surface plate 111 using a clamp member and a screw member ina state in which the surface of the measurement object S is located inthe measurement region V.

The holding section 120 is provided to extend upward from one endportion of the setting section 110. The measurement head 200 is attachedto the upper end portion of the holding section 120 to be opposed to theupper surface of the optical surface plate 111. In this case, since themeasurement head 200 and the setting section 110 are held by the holdingsection 120, it is easy to handle the optical-scanning-height measuringdevice 400. It is unnecessary to separately prepare a fixture for fixingthe measurement head 200. Further, it is possible to easily position themeasurement object S in the measurement region V by placing themeasurement object S on the optical surface plate 111 on the settingsection 110.

As shown in FIG. 1, the lift 130 is provided on the inside of theholding section 120. The lift 130 can move the measurement head 200 inthe up-down direction (the height direction of the measurement object S)with respect to the measurement object S on the optical surface plate111. The measurement head 200 includes a control board 210, an imagingsection 220, an optical section 230, a light guide section 240, areference section 250, a focusing section 260, and a scanning section270. The control board 210 includes, for example, a CPU (centralprocessing unit), a ROM (read only memory), and a RAM (random accessmemory). The control board 210 may be configured by a microcomputer.

The control board 210 is connected to the processing device 300. Thecontrol board 210 controls the operations of the lift 130, the imagingsection 220, the optical section 230, the reference section 250, thefocusing section 260, and the scanning section 270 on the basis of acommand by the processing section 300. The control board 210 givesvarious kinds of information acquired from the imaging section 220, theoptical section 230, the reference section 250, the focusing section260, and the scanning section 270 to the processing device 300. Theimaging section 220 generates image data of the measurement object S byimaging the measurement object S placed on the optical surface plate 111and gives the generated image data to the control board 210.

The optical section 230 emits emission light having temporally lowcoherency to the light guide section 240. The light guide section 240divides the emission light from the optical section 230 into referencelight and measurement light, guides the reference light to the referencesection 250, and guides the measurement light to the focusing section260. The reference section 250 reflects the reference light to the lightguide section 240. The focusing section 260 focuses the measurementlight that passes through the focusing section 260. The scanning section270 scans the measurement light focused by the focusing section 260 tothereby irradiate the measurement light on a desired portion of themeasurement object S.

A part of the measurement light irradiated on the measurement object Sis reflected by the measurement object S and guided to the light guidesection 240 through the scanning section 270 and the focusing section260. The light guide section 240 generates interference light of thereference light reflected by the reference section 250 and themeasurement light reflected by the measurement object S and guides theinterference light to the optical section 230. The optical section 230detects a received light amount for each of wavelengths of theinterference light and gives a signal indicating a result of thedetection to the control board 210. Details of the measurement head 200are explained below.

The processing device 300 includes a control section 310, a storingsection 320, an operation section 330, and a display section 340. Thecontrol section 310 includes, for example, a CPU. The storing section320 includes, for example, a ROM, a RAM, and a HDD (hard disk drive). Asystem program is stored in the storing section 320. The storing section320 is used for storage of various data and processing of the data.

The control section 310 gives, on the basis of the system program storedin the storing section 320, a command for controlling the operations ofthe imaging section 220, the optical section 230, the reference section250, the focusing section 260, and the scanning section 270 of themeasurement head 200 to the control board 210. The control section 310acquires various kinds of information from the control board 210 of themeasurement head 200 and causes the storing section 320 to store thevarious kinds of information.

The operation section 330 includes a pointing device such as a mouse, atouch panel, a trackball, or a joystick and a keyboard. The operationsection 330 is operated by a user in order to give an instruction to thecontrol section 310. The display section 340 includes, for example, anLCD (liquid crystal display) panel or an organic EL(electroluminescence) panel. The display section 340 displays an imagebased on image data stored in the storing section 320, a measurementresult, and the like.

(2) The Lift and the Light Guide Section

FIG. 3 is a block diagram showing the configurations of the standsection 100 and the measurement head 200. In FIG. 3, detailedconfigurations of the lift 130, the optical section 230, and the lightguide section 240 are shown. As shown in FIG. 3, the lift 130 includes adriving section 131, a driving circuit 132, and a reading section 133.

The driving section 131 is, for example, a motor. As indicated by athick arrow in FIG. 3, the driving section 131 moves the measurementhead 200 in the up-down direction with respect to the measurement objectS on the optical surface plate 111. Consequently, it is possible toadjust an optical path length of measurement light over a wide range.The optical path length of the measurement light is the length of anoptical path from the time when the measurement light is output from aport 245 d of the light guide section 240 explained below until themeasurement light reflected by the measurement object S is input to theport 245 d.

The driving circuit 132 is connected to the control board 210. Thedriving circuit 132 drives the driving section 131 on the basis of thecontrol by the control board 210. The reading section 133 is, forexample, an optical linear encoder. The reading section 133 reads adriving amount of the driving section 131 to thereby detect a positionin the up-down direction of the measurement head 200. The readingsection 133 gives a result of the detection to the control board 210.

The optical section 230 includes a light emitting section 231 and ameasuring section 232. The light emitting section 231 includes, forexample, an SLD (super luminescent diode) as a light source and emitsemission light having relatively low coherency. Specifically, thecoherency of the emission light is higher than the coherency of light orwhite light emitted by an LED (light emitting diode) and lower than thecoherency of laser light. Therefore, the emission light has a wavelengthband width smaller than the wavelength band width of the light or thewhite light emitted by the LED and larger than the wavelength band widthof the laser light. The emission light from the optical section 230 isinput to the light guide section 240.

Interference light from the light guide section 240 is output to themeasuring section 232. FIG. 4 is a schematic diagram showing theconfiguration of the measuring section 232. As shown in FIG. 4, themeasuring section 232 includes lenses 232 a and 232 c, a spectralsection 232 b, and a light receiving section 232 d. Interference lightoutput from an optical fiber 242 of the light guide section 240explained below passes through the lens 232 a to thereby besubstantially collimated and made incident on the spectral section 232b. The spectral section 232 b is, for example, a reflective diffractiongrating. Light made incident on the spectral section 232 b is spectrallydispersed to reflect at angles different for each of wavelengths andpasses through the lens 232 c to thereby be focused on one-dimensionalpositions different for each of the wavelengths.

The light receiving section 232 d includes, for example, an imagingelement (a one-dimensional line sensor) in which a plurality of pixelsare one-dimensionally arrayed. The imaging element may be amulti-division PD (photodiode), a CCD (charge coupled device) camera, ora CMOS (complementary metal oxide semiconductor) image sensor or may beother elements. The light receiving section 232 d is disposed such thata plurality of pixels of the imaging element respectively receive lightsin a different focusing positions different for each of wavelengthsformed by the lens 232 c.

Analog electric signals corresponding to received light amounts(hereinafter referred to as light reception signals) are output from thepixels of the light receiving section 232 d and given to the controlboard 210 shown in FIG. 3. Consequently, the control board 210 acquiresdata indicating a relation between the pixels of the light receivingsection 232 d (the wavelength of interference light) and the receivedlight amount. The control board 210 performs a predetermined arithmeticoperation and predetermined processing on the data to thereby calculateheight of a portion of the measurement object S.

As shown in FIG. 3, the light guide section 240 includes four opticalfibers 241, 242, 243, and 244, a fiber coupler 245, and a lens 246. Thefiber coupler 245 has a so-called 2×2 configuration and includes fourports 245 a, 245 b, 245 c, and 245 d and a main body section 245 e. Theports 245 a and 245 b and the ports 245 c and 245 d are provided in themain body section 245 e to be opposed to each other across the main bodysection 245 e.

The optical fiber 241 is connected between the light emitting section231 and the port 245 a. The optical fiber 242 is connected between themeasuring section 232 and the port 245 b. The optical fiber 243 isconnected between the reference section 250 and the port 245 c. Theoptical fiber 244 is connected between the focusing section 260 and theport 245 d. Note that, in this embodiment, the optical fiber 243 islonger than the optical fibers 241, 242, and 244. The lens 246 isdisposed on an optical path of the optical fiber 243 and the referencesection 250.

The emission light from the light emitting section 231 is divided by thelight guide section 240 and output as measurement light and referencelight. Specifically, the emission light from the light emitting section231 is input to the port 245 a through the optical fiber 241. A part ofthe emission light input to the port 245 a is output from the port 245 cas reference light. The reference light passes through the optical fiber243 and the lens 246 to thereby be substantially collimated and guidedto the reference section 250. The reference light reflected by thereference section 250 is input to the port 245 c through the lens 246and the optical fiber 243.

Another part of the emission light input to the port 245 a is outputfrom the port 245 d as measurement light. The measurement light isirradiated on the measurement object S through the optical fiber 244,the focusing section 260, and the scanning section 270. A part of themeasurement light reflected by the measurement object S is input to theport 245 d through the scanning section 270, the focusing section 260,and the optical fiber 244.

Interference light is generated by the reference light returning fromthe reference section 250 and input to the port 245 c and themeasurement light returning from the measurement object S and input tothe port 245 d. The generated interference light is output from the port245 b and guided to the measuring section 232 through the optical fiber242.

(3) The Reference Section

FIG. 5 is a schematic diagram showing the configuration of the referencesection 250. As shown in FIG. 5, the reference section 250 includes asupporting section 251, movable sections 252 a and 252 b, reflectingmembers 253, 254 a, 254 b, and 254 c, driving sections 255 a and 255 b,driving circuits 256 a and 256 b, and reading sections 257 a and 257 b.

The supporting section 251 is fixed to a main body of the measurementhead 200. Linearly extending two linear guides 251 g are attached to thesupporting section 251. The two linear guides 251 g are fixed to thesupporting section 251 such that both of the linear guides 251 g extendin one direction and are arranged side by side in one direction. Morespecifically, the two linear guides 251 g are fixed to the supportingsection 251 such that the two linear guides 251 g are parallel to eachother and one linear guide 251 g is located on an extended line of theother linear guide 251 g. The movable section 252 a and 252 b arerespectively attached to the two linear guides 251 g and supported bythe supporting section 251 to be capable of moving on the linear guides251 g corresponding to the movable sections 252 a and 252 b along adirection in which the linear guides 251 g extend.

The reflecting member 253 is attached to the supporting section 251 andfixed. The reflecting members 254 a and 254 c are attached to themovable section 252 a. The reflecting member 254 b is attached to themovable section 252 b. The reflecting member 254 c is used as areference body. In this embodiment, the reflecting member 254 c isconfigured by a corner cube reflector. The corner cube reflectorreflects light in an original direction irrespective of an incidentdirection. Therefore, it is possible to accurately and easily set anoptical path of the reference light in the reference section 250. Notethat the reflecting member 254 c is not limited to the corner cubereflector. A reflection prism or the like may be used.

The reference light output from the optical fiber 243 is substantiallycollimated by passing through the lens 246 and thereafter sequentiallyreflected by the reflecting member 253, the reflecting member 254 a, thereflecting member 254 b, and the reflecting member 254 c. The referencelight reflected by the reflecting member 254 c is sequentially reflectedby the reflecting member 254 b, the reflecting member 254 a, and thereflecting member 253 and input to the optical fiber 243 through thelens 246.

The driving sections 255 a and 255 b are, for example, voice coilmotors. As indicated by white arrows in FIG. 5, the driving sections 255a and 255 b move the movable sections 252 a and 252 b with respect tothe supporting section 251 along the direction in which the linearguides 251 g extend. In this case, in a direction parallel to the movingdirection of the movable sections 252 a and 252 b, the distance betweenthe reflecting member 253 and the reflecting member 254 a, the distancebetween the reflecting member 254 a and the reflecting member 254 b, andthe distance between the reflecting member 254 b and the reflectingmember 254 c change. Consequently, it is possible to adjust an opticalpath length of the reference light. Note that the driving sections 255 aand 255 b may be configured by other driving mechanisms such as steppingmotors or piezoelectric motors instead of the voice coil motors.

The optical path length of the reference light is the length of anoptical path from the time when the reference light is output from theport 245 c shown in FIG. 3 until the reference light reflected by thereflecting member 254 c is input to the port 245 d. When a differencebetween the optical path length of the reference light and the opticalpath length of the measurement light is equal to or smaller than a fixedvalue, interference light of the reference light and the measurementlight is output from the port 245 b shown in FIG. 3.

The driving circuits 256 a and 256 b are connected to the control board210 shown in FIG. 3. The driving circuits 256 a and 256 b respectivelyoperate the driving sections 255 a and 255 b on the basis of the controlby the control board 210. At this point, the driving circuits 256 a and256 b move the movable sections 252 a and 252 b with respect to thesupporting section 251 in opposite directions each other. In this case,even if the movable sections 252 a and 252 b intermittently repeatmovement and stop, the position of the center of gravity of theoptical-scanning-height measuring device 400 hardly changes.Consequently, the position of the center of gravity of theoptical-scanning-height measuring device 400 is stabilized during themovement of the movable sections 252 a and 252 b.

The reading sections 257 a and 257 b are, for example, optical linearencoders. The reading section 257 a reads a driving amount of thedriving section 255 a to thereby detect a relative position of themovable section 252 a with respect to the supporting section 251 andgives a result of the detection to the control board 210. The readingsection 257 b reads a driving amount of the driving section 255 b tothereby detect a relative position of the movable section 252 b withrespect to the supporting section 251 and gives a result of thedetection to the control board 210.

In the reference section 250 explained above, a total of the weight ofone movable section 252 a and the weight of the reflecting members 254 aand 254 c attached to the movable section 252 a is desirably set to bein a fixed range from a total of the weight of the other movable section252 b and the weight of the reflecting member 254 b attached to themovable section 252 b. The fixed range is a range in which two totalvalues can be regarded as equal or substantially equal. In this case,the position of the center of gravity of the optical-scanning-heightmeasuring device 400 is further stabilized during the movement of themovable sections 252 a and 252 b.

In this embodiment, the movable sections 252 a and 252 b move inopposite directions each other along the direction in which the linearguides 251 g extend. However, the present invention is not limited tothis. Only one of the movable section 252 a and the movable section 252b may move along the direction in which the linear guide 251 g extendsand the other may not move. In this case, the unmoving other movablesection 252 a or 252 b may be fixed to the fixed section 251 or the mainbody of the measurement head 200 rather than the linear guides 251 g asan unmovable section.

(4) The Focusing Section

FIG. 6 is a schematic diagram showing the configuration of the focusingsection 260. As shown in FIG. 6, the focusing section 260 includes afixed section 261, a movable section 262, a movable lens 263, a drivingsection 264, a driving circuit 265, and a reading section 266. Themovable section 262 is attached to the fixed section 261 to be capableof moving along one direction. The movable lens 263 is attached to themovable section 262. The movable lens 263 is used as an objective lensand focuses the measurement light that passes through the movable lens263.

The measurement light output from the optical fiber 244 is guided to thescanning section 270 shown in FIG. 3 through the movable lens 263. Apart of the measurement light reflected by the measurement object Sshown in FIG. 3 passes through the scanning section 270 and thereafteris input to the optical fiber 244 through the movable lens 263.

The driving section 264 is, for example, a voice coil motor. Asindicated by a thick arrow in FIG. 6, the driving section 264 moves themovable section 262 in one direction (a traveling direction of themeasurement light) with respect to the fixed section 261 on an opticalpath of the measurement light. Consequently, it is possible to locate afocus of the measurement light on the surface of the measurement objectS.

The driving circuit 265 is connected to the control board 210 shown inFIG. 3. The driving circuit 265 operates the driving section 264 on thebasis of the control by the control board 210. The reading section 266is, for example, an optical linear encoder. The reading section 266reads a driving amount of the driving section 264 to thereby detect arelative position of the movable section 262 (the movable lens 263) withrespect to the fixed section 261. The reading section 266 gives a resultof the detection to the control board 210.

The control board 210 controls the driving circuit 265 on the basis ofthe detection result of the reading section 266 and distance informationcalculated by the distance-information calculating section 12 (FIG. 12)explained below such that the measurement light is focused on thesurface of the measurement object S. In this way, the measurement lightis focused on the surface of the measurement object. Consequently,measurement accuracy of the optical-scanning-height measuring device isimproved.

Note that a collimator lens that collimates the measurement light outputfrom the optical fiber 244 may be disposed between the optical fiber 244and the movable lens 263. In this case, the measurement light madeincident on the movable lens 263 is collimated. A beam diameter of themeasurement light does not change irrespective of a moving position ofthe movable lens 263. Therefore, it is possible to form the movable lens263 small.

(5) The Scanning Section

FIG. 7 is a schematic diagram showing the configuration of the scanningsection 270. As shown in FIG. 7, the scanning section 270 includesdeflecting sections 271 and 272, driving circuits 273 and 274, andreading sections 275 and 276. The deflecting section 271 is configuredby, for example, a galvanometer mirror and includes a driving section271 a and a reflecting section 271 b. The driving section 271 a is, forexample, a motor having a rotating shaft in a substantiallyperpendicular direction. The reflecting section 271 b is attached to therotating shaft of the driving section 271 a. The measurement lightpassed through the optical fiber 244 to the focusing section 260 shownin FIG. 3 is guided to the reflecting section 271 b. The driving section271 a rotates, whereby a reflection angle of the measurement lightreflected by the reflecting section 271 b changes in a substantiallyhorizontal plane.

Like the deflecting section 271, the deflecting section 272 isconfigured by, for example, a galvanometer mirror and includes a drivingsection 272 a and a reflecting section 272 b. The driving section 272 ais, for example, a motor including a rotating shaft in the horizontaldirection. The reflecting section 272 b is attached to the rotatingshaft of the driving section 272 a. The measurement light reflected bythe reflecting section 271 b is guided to the reflecting section 272 b.The driving section 272 a is rotated, whereby a reflection angle of themeasurement light reflected by the reflecting section 272 b changes in asubstantially perpendicular surface.

In this way, the driving sections 271 a and 272 a rotate, whereby themeasurement light is scanned in two directions orthogonal to each otheron the surface of the measurement object S shown in FIG. 3.Consequently, it is possible to irradiate the measurement light on anyposition on the surface of the measurement object S. The measurementlight irradiated on the measurement object S is reflected on the surfaceof the measurement object S. A part of the reflected measurement lightis sequentially reflected by the reflecting section 272 b and thereflecting section 271 b and thereafter guided to the focusing section260 shown in FIG. 3.

The driving circuits 273 and 274 are connected to the control board 210shown in FIG. 3. The driving circuits 273 and 274 respectively drive thedriving sections 271 a and 272 a on the basis of the control by thecontrol board 210.

In this embodiment, when a position where the measurement light shouldbe irradiated is specified, the control board 210 controls the drivingsections 271 a and 272 a to irradiate the measurement light on aplurality of positions in a very small partial including or surroundingthe specified position.

FIG. 8 is an enlarged perspective view schematically showing a state inwhich the measurement light is irradiated on a specified position on thesurface of the measurement object S. In an example shown in FIG. 8, asindicated by a thick alternate long and short dash line, measurementlight MB emitted from the scanning section 270 is scanned to besequentially irradiated on a plurality of portions P in an annularpartial region PA surrounding a specified position TP on the surface ofthe measurement object S.

The outer diameter of the partial region PA in this example is set to,for example, 0.1 mm or more and 0.2 mm or less. Note that the outerdiameter of the partial region PA may be capable of being set by theuser or may be set in advance during factory shipment of theoptical-scanning-height measuring device 400.

As explained above, the outer diameter of the partial region PA isbasically set to an extremely small value. Therefore, since the partialregion PA is very small, for the user, the partial region PA isrecognized as one point rather than an annular shape. Note that, in thisexample, a time required to scan the measurement light MB around thepartial region PA once is set to approximately 50 msec.

The reading sections 275 and 276 are, for example, an optical rotaryencoder. The reading section 275 reads a driving amount of the drivingsection 271 a to thereby detect an angle of the reflecting section 271 band gives a result of the detection to the control board 210. Thereading section 276 reads a driving amount of the driving section 272 ato thereby detect an angle of the reflecting section 272 b and gives aresult of the detection to the control board 210. In this case, thecontrol board 210 detects angles of the reflecting sections 271 b and272 b corresponding to the partial region PA on the basis of a detectionresult given from the reading sections 275 and 276 when the measurementlight MB is sequentially irradiated on the plurality of portions P inthe partial region PA. For example, the control board 210 detects, asthe angles of the reflecting sections 271 b and 272 b corresponding tothe position TP and the partial region PA, an average of angles of thereflecting section 271 b and an average of angles of the reflectingsection 272 b that change when the measurement light MB is sequentiallyirradiated on the plurality of portions P in the partial region PA.

In this example, the partial region PA has an annular shape. In thiscase, it is possible to smoothly irradiate the measurement light MB onthe plurality of portions P in the partial region PA by annularlyscanning the measurement light MB along the circumferential direction ofthe partial region PA.

Note that the shape of the partial region PA is not limited to theannular shape explained above. FIGS. 9A to 9C are schematic diagramsshowing other examples of the partial region PA. The partial region PAmay have a square shape surrounding the position TP as shown in FIG. 9Aor may have a triangular shape surrounding the position TP as shown inFIG. 9B. The partial region PA may have a cross shape including theposition TP as shown in FIG. 9C. In the partial region PA shown in FIGS.9A to 9C, a maximum dimension of the external shape of the partialregion PA is desirably set to, for example, 0.1 mm or more and 0.2 mm orless.

As explained above, the partial region PA is very small enough to berecognized as one point by the user. Therefore, in the followingexplanation, it is assumed that, according to necessity, when a positionwhere the measurement light should be irradiated is specified, thescanning section 270 irradiates the measurement light on the specifiedposition.

(6) Operation Modes

The optical-scanning-height measuring device 400 shown in FIG. 1operates in an operation mode selected from a plurality of operationmodes by the user. Specifically, the operation modes include a settingmode, a measurement mode, and a height gauge mode. FIG. 10 is a diagramshowing an example of a selection screen 341 displayed on the displaysection 340 of the optical-scanning-height measuring device 400.

As shown in FIG. 10, a setting button 341 a, a measurement button 341 b,and a height gauge button 341 c are displayed on the selection screen341 of the display section 340. The user operates the setting button 341a, the measurement button 341 b, and the height gauge button 341 c usingthe operation section 330 shown in FIG. 1, whereby theoptical-scanning-height measuring device 400 operates respectively inthe setting mode, the measurement mode, and the height gauge mode.

In the following explanation, among users, a skilled user who managesmeasurement work of the measurement object S is referred to asmeasurement manager as well and a user who performs the measurement workof the measurement object S under the management of the measurementmanger is referred to as measurement operator as appropriate. Thesetting mode is mainly used by the measurement manager. The measurementmode is mainly used by the measurement operator.

In the optical-scanning-height measuring device 400, a three-dimensionalcoordinate system peculiar to a space including the measurement region Vshown in FIG. 2 is defined in advance by an X axis, a Y axis, and a Zaxis. The X axis and the Y axis are parallel to the optical surfaceplate 111 shown in FIG. 2 and orthogonal to each other. The Z axis isorthogonal to the X axis and the Y axis. In the operation modes, data ofa coordinate specified by the coordinate system and data of a planecoordinate on an image acquired by imaging of the imaging section 220are transmitted between the control section 310 and the control board210. FIGS. 11A to 11C are diagrams showing contents of data transmittedbetween the control section 310 and the control board 210 in theoperation modes.

In the setting mode, the measurement manager can register informationconcerning a desired measurement object S in the optical-scanning-heightmeasuring device 400. Specifically, the measurement manager places thedesired measurement object S on the optical surface plate 111 shown inFIG. 2 and images the measurement object S with the imaging section 220shown in FIG. 3. The measurement manager designates, on the image, as ameasurement point, a portion that should be measured of the measurementobject S displayed on the display section 340 shown in FIG. 1. In thiscase, as shown in FIG. 11A, the control section 310 gives a planecoordinate (Ua, Va) specified by the designated measurement point on theimage to the control board 210.

The control board 210 specifies a three-dimensional coordinate (Xc, Yc,Zc) of a position corresponding to the plane coordinate (Ua, Va) in themeasurement region V shown in FIG. 2 and gives the specifiedthree-dimensional coordinate (Xc, Yc, Zc) to the control section 310.The control section 310 causes the storing section 320 shown in FIG. 1to store the three-dimensional coordinate (Xc, Yc, Zc) given by thecontrol board 210. The control section 310 calculates height of theportion corresponding to the measurement point on the basis ofinformation such as the three-dimensional coordinate (Xc, Yc, Zc) storedin the storing section 320 and a reference plane explained below andcauses the storing section 320 to store a result of the calculation.

The measurement mode is used to measure the height of the portioncorresponding to the measurement point concerning the measurement objectS of the same type as the measurement object S, the information of whichis registered in the optical-scanning-height measuring device 400 in thesetting mode. Specifically, the measurement operator places, on theoptical surface plate 111, the measurement object S of the same type asthe measurement object S, the information of which is registered in theoptical-scanning-height measuring device 400 in the setting mode, andimages the measurement object S with the imaging section 220. In thiscase, as shown in FIG. 11B, the control section 310 gives athree-dimensional coordinate (Xc, Yc, Zc) stored in the storing section320 in the setting mode to the control board 210.

The control board 210 calculates a three-dimensional coordinate (Xb, Yb,Zb) of the portion of the measurement object S corresponding to themeasurement point on the basis of the acquired three-dimensionalcoordinate (Xc, Yc, Zc). The control board 210 gives the calculatedthree-dimensional coordinate (Xb, Yb, Zb) to the control section 310.The control section 310 calculates height of the portion correspondingto the measurement point on the basis of information such as thethree-dimensional coordinate (Xb, Yb, Zb) given by the control board 210and the reference plane explained below. The control section 310 causesthe display section 340 shown in FIG. 1 to display a result of thecalculation.

In this way, in the measurement mode, the measurement operator canacquire the height of the portion that should be measured of themeasurement object S without designating the portion. Therefore, evenwhen the measurement operator is not skilled, it is possible to easilyand accurately measure a shape of a desired portion of the measurementobject. The three-dimensional coordinate (Xc, Yc, Zc) is stored in thestoring section 320 in the setting mode. Therefore, in the measurementmode, it is possible to quickly specify the portion corresponding to themeasurement point on the basis of the stored three-dimensionalcoordinate (Xc, Yc, Zc).

In this embodiment, in the setting mode, the three-dimensionalcoordinate (Xc, Yc, Zc) corresponding to the plane coordinate (Ua, Va)is specified and stored in the storing section 320. However, the presentinvention is not limited to this. In the setting mode, a planecoordinate (Xc, Yc) corresponding to the plane coordinate (Ua, Va) maybe specified and a component Zc of the Z axis may be not specified. Inthis case, the specified plane coordinate (Xc, Yc) is stored in thestoring section 320. In the measurement mode, the plane coordinate (Xc,Yc) stored in the storing section 320 is given to the control board 210.

The height gauge mode is used by the user to designate a desired portionof the measurement object S as the measurement point on the screen andmeasure height of the portion while confirming the measurement object Son the screen. Specifically, the user places the desired measurementobject S on the optical surface plate 111 and images the measurementobject S with the imaging section 220. The user designates, as themeasurement point, a portion that should be measured on an image of themeasurement object S displayed on the display section 340. In this case,as shown in FIG. 11C, the control section 310 gives a plane coordinate(Ua, Va) specified by the designated measurement point on the image tothe control board 210.

The control board 210 specifies a three-dimensional coordinate (Xc, Yc,Zc) of the position corresponding to the plane coordinate (Ua, Va) inthe measurement region V shown in FIG. 2 and calculates, on the basis ofthe specified three-dimensional coordinate (Xc, Yc, Zc), athree-dimensional coordinate (Xb, Yb, Zb) of the portion of themeasurement object S corresponding to the measurement point. The controlboard 210 gives the calculated three-dimensional coordinate (Xb, Yb, Zb)to the control section 310. The control section 310 calculates height ofthe portion corresponding to the measurement point on the basis ofinformation such as the three-dimensional coordinate (Xb, Yb, Zb) givenby the control board 210 and the reference plane explained below andcauses the display section 340 to display a result of the calculation.

In the storing section 320 shown in FIG. 1, coordinate conversioninformation and position conversion information are stored in advance.The coordinate conversion information indicates plane coordinates (Xc,Yc) corresponding to plane coordinates (Ua, Va) in positions in theheight direction (the Z-axis direction) in the measurement region V. Thecontrol board 210 can irradiate the measurement light on a desiredposition in the measurement region V by controlling positions of themovable sections 252 a and 252 b shown in FIG. 5 and angles of thereflecting sections 271 b and 272 b shown in FIG. 7. The positionconversion information indicates a relation between the coordinates inthe measurement region V and the positions of the movable sections 252 aand 252 b and the angles of the reflecting sections 271 b and 272 b.

A control system configured by the control section 310 and the controlboard 210 can specify a three-dimensional coordinate (Xc, Yc, Zc) and athree-dimensional coordinate (Xb, Yb, Zb) of a position corresponding tothe measurement position by using the coordinate conversion informationand the position conversion information. Details of the coordinateconversion information and the position conversion information areexplained below.

(7) A Control System of the Optical-Scanning-Height Measuring Device (a)Overall Configuration of the Control System

FIG. 12 is a block diagram showing the control system of theoptical-scanning-height measuring device 400 shown in FIG. 1. As shownin FIG. 12, the control system 410 includes a reference-image acquiringsection 1, a position-information acquiring section 2, a driving controlsection 3, a reference-plane acquiring section 4, an allowable-valueacquiring section 5, a registering section 6, a deflecting-directionacquiring section 7, a detecting section 8, and an image analyzingsection 9. The control system 410 further includes a reference-positionacquiring section 10, a light-reception-signal acquiring section 11, adistance-information calculating section 12, a coordinate calculatingsection 13, a determining section 14, a height calculating section 15, ameasurement-image acquiring section 16, a correcting section 17, aninspecting section 18, and a report preparing section 19.

The control board 210 and the control section 310 shown in FIG. 1execute the system program stored in the storing section 320, wherebyfunctions of the components of the control system 410 are realized. InFIG. 12, a flow of common processing in all the operation modes isindicated by solid lines, a flow of processing in the setting mode isindicated by alternate long and short dash lines, and a flow ofprocessing in the measurement mode is indicated by dotted lines. Thesame applies in FIG. 37 referred to below. A flow of processing in theheight gauge mode is substantially equal to a flow of processing in thesetting mode. In the following explanation, to facilitate understanding,the components of the control system 410 in the setting mode and themeasurement mode are separately explained.

(b) The Setting Mode

The measurement administrator places a desired measurement object S onthe optical surface plate 111 shown in FIG. 2 and images the measurementobject S with the imaging section 220 shown in FIG. 3. Thereference-image acquiring section 1 acquires, as reference image data,image data generated by the imaging section 220 and causes the displaysection 340 shown in FIG. 1 to display, as a reference image, an imagebased on the acquired reference image data. The reference imagedisplayed on the display section 340 may be a still image or may be amoving image that is sequentially updated. The measurement manager candesignate, as the reference point, a portion that should be measured anddesignate a reference point on the reference image displayed on thedisplay section 340. The reference point is a point for deciding areference plane serving as a reference in calculating height of themeasurement object S.

The position-information acquiring section 2 receives designation of themeasurement point on the reference image acquired by the reference-imageacquiring section 1 and acquires a position (the plane coordinate (Ua,Va) explained above) of the received measurement point. Theposition-information acquiring section 2 receives designation of areference point using the reference image and acquires a position of thereceived reference point. The position-information acquiring section 2is also capable of receiving a plurality of measurement points andcapable of receiving a plurality of reference points.

The driving control section 3 acquires a position of the measurementhead 200 from the reading section 133 of the lift 130 shown in FIG. 3and controls the driving circuit 132 shown in FIG. 3 on the basis of theacquired position of the measurement head 200. Consequently, themeasurement head 200 is moved to a desired position in the up-downdirection. The driving control section 3 acquires a position of themovable lens 263 from the reading section 266 of the focusing section260 shown in FIG. 6 and controls the driving circuit 265 shown in FIG. 6on the basis of the acquired position of the movable lens 263.Consequently, the movable lens 263 is moved such that the measurementlight is focused near the surface of the measurement object S.

The driving control section 3 controls the driving circuits 273 and 274shown in FIG. 7 and the driving circuits 256 a and 256 b shown in FIG. 5on the basis of the position conversion information stored in thestoring section 320 shown in FIG. 1 and the position acquired by theposition-information acquiring section 2. Consequently, the angles ofthe reflecting sections 271 b and 272 b of the deflecting sections 271and 272 shown in FIG. 7 are adjusted. The measurement light isirradiated on the portions of the measurement object S corresponding tothe measurement point and the reference point.

The driving control section 3 adjusts, according to the change in theoptical path length of the measurement light, the optical path length ofthe reference light to reduce a difference between the optical pathlength of the measurement light and the optical path length of thereference light to a fixed value or less. More specifically, in thedriving control section 3, a threshold concerning the difference betweenthe optical path length of the measurement light and the optical pathlength of the reference light is set in advance such that appropriateinterference light is obtained. Therefore, when the difference betweenthe optical path length of the measurement light and the optical pathlength of the reference light calculated by the distance-informationcalculating section 12 explained below is equal to or smaller than thethreshold, the driving control section 3 controls the driving circuits256 a and 256 b shown in FIG. 5 to maintain the optical path length ofthe reference light. On the other hand, when the difference between theoptical path length of the measurement light and the optical path lengthof the reference light is larger than the threshold, the driving controlsection 3 controls the driving circuits 256 a and 256 b shown in FIG. 5to change the optical path length of the reference light. Consequently,it is possible to easily adjust the optical path length of the referencelight to appropriate size. Therefore, a measurable height range of themeasurement object S is expanded.

According to the operation of the driving control section explainedabove, coordinates of the portions of the measurement object Scorresponding to the measurement point and the reference point arecalculated by the coordinate calculating section 13 as explained below.Details of the operation of the driving control section 3 are explainedbelow. In the following explanation, processing for calculating acoordinate of the portion of the measurement object S corresponding tothe measurement point is explained. However, processing for calculatinga coordinate of the portion of the measurement object S corresponding tothe reference point is the same as the processing for calculating acoordinate of the portion of the measurement object S corresponding tothe measurement point.

The reference-plane acquiring section 4 acquires a reference plane onthe basis of one or a plurality of coordinates calculated by thecoordinate calculating section 13 according to one or a plurality ofreference points acquired by the position-information acquiring section2. Concerning the measurement point acquired by the position-informationacquiring section 2, the measurement manager can input an allowablevalue for height. The allowable value is used for inspection of themeasurement object S in the measurement mode explained below andincludes a design value and a tolerance from the design value. Theallowable-value acquiring section 5 receives the input allowable value.

The registering section 6 registers the reference image data acquired bythe reference-image acquiring section 1, the position acquired by theposition-information acquiring section 2, and the allowable value set bythe allowable-value acquiring section 5 in association with one another.Specifically, the registering section 6 causes the storing section 320to store registration information indicating a relation among thereference image data, the positions of the measurement point and thereference point, and allowable values corresponding to measurementvalues. A plurality of reference planes may be set. In this case, theregistering section 6 registers, for each of the reference planes, areference point corresponding to the reference plane, a measurementpoint corresponding to the reference plane, and allowable valuescorresponding to the measurement values in association with one another.

The deflecting-direction acquiring section 7 acquires the angles of thereflecting sections 271 b and 272 b respectively from the readingsections 275 and 276 shown in FIG. 7. The detecting section 8 detectsdeflecting directions of the deflecting sections 271 and 272respectively on the basis of the angles of the reflecting sections 271 band 272 b acquired by the deflecting-direction acquiring section 7. Morespecifically, the detecting section 8 detects deflecting directions ofthe deflecting sections 271 and 272 corresponding to the partial regionPA shown in FIG. 8 explained above. The imaging of the imaging section220 is continued, whereby the measurement light on the measurementobject S appears in the reference image. The image analyzing section 9analyzes the reference image data acquired by the reference-imageacquiring section 1. The detecting section 8 detects, on the basis of aresult of the analysis by the image analyzing section 9, a planecoordinate indicating an irradiation position on the reference image ofthe measurement light deflected by the deflecting sections 271 and 272.More specifically, the detecting section 8 detects, for example, a planecoordinate indicating a center position of the plurality of portions Pas an irradiation position on the reference image corresponding to thepartial region PA shown in FIG. 8 explained above.

The reference-position acquiring section 10 acquires positions of themovable sections 252 a and 252 b respectively from the reading sections257 a and 257 b of the reference section 250 shown in FIG. 5. Thelight-reception-signal acquiring section 11 acquires a light receptionsignal from the light receiving section 232 d shown in FIG. 4. Morespecifically, the light-reception-signal acquiring section 11 acquires,for each partial region PA shown in FIG. 8, a light reception signaloutput from the light receiving section 232 d according to incidence ofthe measurement light on the light receiving section 232 d from theplurality of portions P.

The distance-information calculating section 12 integrates a pluralityof light reception signals corresponding to the plurality of portions Pshown in FIG. 8 acquired for each partial region PA shown in FIG. 8 bythe light receiving section 232 d. The distance-information calculatingsection 12 performs, on the basis of the integrated light receptionsignal, predetermined processing on data indicating a relation between awavelength and a received light amount of the interference light. Theprocessing includes frequency axis conversion from a wavelength to awave number and Fourier transform of the wave number.

Note that, after performing the predetermined processing on the dataindicating the relation between the wavelength and the received lightamount of the interference light on the basis of the light receptionsignal corresponding to the respective plurality of portions P, thedistance-information calculating section 12 may integrate a plurality ofdata after the processing corresponding to the respective plurality ofportions P instead of integrating the plurality of light receptionsignals corresponding to the plurality of portions P.

The distance-information calculating section 12 calculates a differencebetween the optical path length of the measurement light and the opticalpath length of the reference light on the basis of the data obtained bythe processing and the positions of the movable sections 252 a and 252 bacquired by the reference-position acquiring section 10. Thedistance-information calculating section 12 calculates, on the basis ofthe calculated difference, distance information indicating the distancebetween the emitting position of the measurement light in themeasurement head 200 and the irradiation position of the measurementlight in the measurement object S shown in FIG. 2. The emitting positionof the measurement light in the measurement head 200 is, for example,the position of the port 245 d of the light guide section 240 shown inFIG. 3.

The coordinate calculating section 13 calculates a three-dimensionalcoordinate (Xc, Yc, Zc) of the irradiation position of the measurementlight on the measurement object S on the basis of the deflectingdirections of the deflecting sections 271 and 272 detected by thedetecting section 8 and the distance information calculated by thedistance-information calculating section 12. The three-dimensionalcoordinate (Xc, Yc, Zc) of the irradiation position of the measurementlight includes a coordinate Zc in the height direction and a planecoordinate (Xc, Yc) in a plane orthogonal to the height direction.

The coordinate calculating section 13 may calculate, using, for example,the triangulation system, a three-dimensional coordinate of theirradiation position of the measurement light on the measurement objectS on the basis of a plane coordinate indicating an irradiation positionon the reference image of the measurement light detected by thedetecting section 8 and the deflecting directions of the deflectingsections 271 and 272. Alternatively, the coordinate calculating section13 may calculate a three-dimensional coordinate of the irradiationposition of the measurement light on the measurement object S on thebasis of a plane coordinate indicating the irradiation position on thereference image of the measurement light detected by the detectingsection 8 and the distance information calculated by thedistance-information calculating section 12.

The determining section 14 determines whether the measurement light isirradiated on the portion of the measurement object S corresponding tothe measurement point or a portion near the portion. Specifically, thecoordinate calculating section 13 acquires, on the basis of thecalculated coordinate in the height direction and the coordinateconversion information stored in the storing section 320, a planecoordinate (a plane coordinate (Xa′, Ya′) explained below) correspondingthe measurement point registered by the registering section 6. Thedetermining section 14 determines whether the plane coordinate (Xc, Yc)calculated by the coordinate calculating section 13 is present within arange decided in advance from the plane coordinate (Xa′, Ya′)corresponding to the measurement point.

Alternatively, the image analyzing section 9 may perform an imageanalysis of the reference image data to thereby specify a planecoordinate (a plane coordinate (Uc, Vc) explained below) of theirradiation position of the measurement light in the reference image. Inthis case, the determining section 14 determines whether the planecoordinate (Uc, Vc) of the irradiation position of the measurement lightspecified by the image analyzing section 9 is present within a rangedecided in advance from the plane coordinate (Ua, Va) of the measurementpoint registered by the registering section 6.

When the determining section 14 determines that the measurement light isnot irradiated on the portion of the measurement object S correspondingto the measurement point and the portion near the portion, the drivingcontrol section 3 controls the driving circuits 273 and 274 shown inFIG. 7 and the driving circuits 256 a and 256 b shown in FIG. 5 to movethe irradiation position of the measurement light. When the determiningsection 14 determines that the measurement light is irradiated on theportion of the measurement object S corresponding to the measurementpoint and the portion near the portion, the driving control section 3controls the driving circuits 273 and 274 and the driving circuits 256 aand 256 b to fix the irradiation position of the measurement light.

The coordinate calculating section 13 gives the coordinate calculatedconcerning the reference point to the reference-plane acquiring Section4. The height calculating section 15 calculates, on the basis of thethree-dimensional coordinate (Xc, Yc, Zc) calculated by the coordinatecalculating section 13 according to the measurement point, height of theportion of the measurement object S based on the reference planeacquired by the reference-plane acquiring section 4. For example, whenthe reference plane is a plane, the height calculating section 15calculates, as height, length from the reference plane tothree-dimensional coordinate (Xc, Yc, Zc) in the perpendicular of thereference plane passing the three-dimensional coordinate (Xc, Yc, Zc).The height calculating section 15 causes the display section 340 todisplay the calculated height. The registering section 6 registers, asregistration information, the three-dimensional coordinate (Xc, Yc, Zc)calculated by the coordinate calculating section 13 and the heightcalculated by the height calculating section 15 in association with thereference image data, the position of the measurement point, theposition of the reference point, and the allowable value.

(c) The Measurement Mode

The measurement operator places the measurement object S of the sametype as the measurement object S, the registration information of whichis registered in the setting mode, on the optical surface plate 111shown in FIG. 2 and images the measurement object S with the imagingsection 220 shown in FIG. 3. The measurement-image acquiring section 16acquires, as measurement image data, image data generated by the imagingsection 220 and causes the display section 340 shown in FIG. 1 todisplay, as a measurement image, an image based on the acquiredmeasurement image data.

The correcting section 17 corrects deviation of the measurement imagedata with respect to the reference image data on the basis of theregistration information registered by the registering section 6.Consequently, the correcting section 17 sets, in the measurement imagedata, a measurement point and a reference point corresponding to theregistration information registered by the registering section 6.

The driving control section 3 controls the driving circuits 273 and 274shown in FIG. 7 and the driving circuits 256 a and 256 b shown in FIG. 5on the basis of the registration information registered by theregistering section 6 in the setting mode. Consequently,three-dimensional coordinates of portions of the measurement object Scorresponding to the measurement point and the reference point set bythe correcting section 17 are calculated by the coordinate calculatingsection 13. The driving control section 3 performs the control on thebasis of the three-dimensional coordinates and the heights registered inthe setting mode. Therefore, the coordinate calculating section 13 canefficiently calculate the three-dimensional coordinates of the portionsof the measurement object S corresponding to the measurement point andthe reference point set by the correcting section 17.

The kinds of processing by the deflecting-direction acquiring section 7and the detecting section 8 in the measurement mode are respectively thesame as the kinds of processing by the deflecting-direction acquiringsection 7 and the detecting section 8 in the setting mode. Theprocessing by the image analyzing section 9 in the measurement mode isthe same as the processing by the image analyzing section 9 in thesetting mode except that the measurement image data acquired by themeasurement-image acquiring section 16 is used instead of the referenceimage data acquired by the reference-image acquiring section 1. Thekinds of processing by the reference-position acquiring section 10, thelight-reception-signal acquiring section 11, and thedistance-information calculating section 12 in the measurement mode arerespectively the same as the kinds of processing by thereference-position acquiring section 10, the light-reception-signalacquiring section 11, and the distance-information calculating section12 in the setting mode.

The coordinate calculating section 13 calculates a three-dimensionalcoordinate (Xb, Yb, Zb) of the irradiation position of the measurementlight on the measurement object S on the basis of the deflectingdirections of the deflecting sections 271 and 272 detected by thedetecting section 8 and the distance information calculated by thedistance-information calculating section 12. The coordinate calculatingsection 13 may calculate the three-dimensional coordinate (Xb, Yb, Zb)of the irradiation position of the measurement light on the measurementobject S on the basis of the plane coordinate indicating the irradiationposition on the measurement image of the measurement light detected bythe detecting section 8 and the distance information calculated by thedistance-information calculating section 12. The three-dimensionalcoordinate (Xb, Yb, Zb) of the irradiation position of the measurementlight includes a coordinate Zb in the height direction and a planecoordinate (Xb, Yb) in the plane orthogonal to the height direction.

The processing by the determining section 14 in the measurement mode isthe same as the processing by the determining section 14 in the settingmode except that the measurement point set by the correcting section 17is used instead of the measurement point registered by the registeringsection 6 and that the three-dimensional coordinate (Xb, Yb, Zb) is usedinstead of the three-dimensional coordinate (Xc, Yc, Zc). Consequently,the coordinate calculating section 13 calculates a coordinatecorresponding to the reference point set by the correcting section 17.

The reference-plane acquiring section 4 acquires a reference plane onthe basis of a coordinate corresponding to the reference pointcalculated by the coordinate calculating section 13. Theheight-calculating section 15 calculates, on the basis of thethree-dimensional coordinate (Xb, Yb, Zb) calculated by the coordinatecalculating section 13, height of a portion of the measurement object Sbased on the reference plane acquired by the reference-plane acquiringsection 4.

The inspecting section 18 inspects the measurement object S on the basisof the height of the portion of the measurement object S calculated bythe height calculating section 15 and the allowable value registered inthe registering section 6. Specifically, when the calculated height iswithin a-range of the tolerance based on the design value, theinspecting section 18 determines that the measurement object S is anon-defective product. On the other hand, when the calculated height isoutside the range of the tolerance based on the setting value, theinspecting section 18 determines that the measurement object S is adefective product.

The report preparing section 19 prepares a report on the basis of aresult of the inspection by the inspecting section 18 and the referenceimage acquired by the measurement-image acquiring section 16.Consequently, the measurement operator can easily report the inspectionresult concerning the measurement object S to the measurement manager orthe other users using the report. The report is prepared according to adescription format determined in advance. FIG. 13 is a diagram showingan example of the report prepared by the report preparing section 19.

In the description form shown in FIG. 13, a report 420 includes a namedisplay field 421, an image display field 422, a state display field423, a result display field 424, and a guarantee display field 425. Inthe name display field 421, a name (in the example shown in FIG. 13,“inspection result sheet”) of the report 420 is displayed. In the imagedisplay field 422, a measurement image of an inspection target isdisplayed. In the state display field 423, a name of the inspectiontarget, an identification number of the inspection target, a name of ameasurement operator, an inspection date and time, and the like aredisplayed.

In the result display field 424, an inspection result concerning theinspection target is displayed. Specifically, in the result displayfield 424, names, measurement values, and determination results ofvarious inspection items set for the inspection target are displayed ina form of a list table in a state in which the measurement values andthe determination results are associated with design values andtolerances. The guarantee display field 425 is a blank for a signatureor a seal. The measurement operator and the measurement manager canguarantee an inspection result by signing or sealing the guaranteedisplay field 425.

The report preparing section 19 may prepare the report 420 onlyconcerning the measurement object S determined as a non-defectiveproduct by the inspecting section 18. The report 420 is attached to astatement of delivery in order to guarantee the quality of an inspectiontarget product when the inspection target product is delivered to acustomer. The report preparing section 19 may prepare the report 420only concerning the measurement object S determined as a defectiveproduct by the inspecting section 18. The report 420 is used in the owncompany in order to analyze a cause of the determination that theinspection target product is the defective product.

(d) The Height Gauge Mode

The user places a desired measurement object S on the optical surfaceplate 111 shown in FIG. 2 and images the measurement object S with theimaging section 220 shown in FIG. 3. The reference-image acquiringsection 1 acquires image data generated by the imaging section 220 andcauses the display section 340 shown in FIG. 1 to display an image basedon the acquired image data. The user designates, as a measurement point,a portion that should be measured on the image displayed on the displaysection 340.

The position-information acquiring section 2 receives designation of ameasurement point on an image acquired by the reference-image acquiringsection 1 and acquires a position (the plane coordinate (Ua, Va)explained above) of the received measurement point. Theposition-information acquiring section 2 receives designation of areference point using the reference image and acquires a position of thereceived reference point. The position-information acquiring section 2is also capable of receiving a plurality of measurement points andcapable of receiving a plurality of reference points.

The driving control section 3 controls the driving circuits 273 and 274shown in FIG. 7 and the driving circuits 256 a and 256 b shown in FIG. 5on the basis of the position conversion information stored in thestoring section 320 shown in FIG. 1 and the position acquired by theposition-information acquiring section 2. Consequently, measurementlight is irradiated on portions of the measurement object Scorresponding to the measurement point and the reference point and anoptical path length of reference light is adjusted.

According to the operation of the driving control section explainedabove, coordinates of the portions of the measurement object Scorresponding to the measurement point and the reference point arecalculated by the coordinate calculating section 13. The reference-planeacquiring section 4 acquires a reference plane on the basis of thecoordinate calculated by the coordinate-calculating section 13 accordingto the reference point acquired by the position-information acquiringsection 2.

The kinds of processing by the deflecting-direction acquiring section 7,the detecting section 8, the image analyzing section 9, thereference-position acquiring section 10, the light-reception-signalacquiring section 11, and the distance-information calculating section12 in the height gauge mode are respectively the same as the kinds ofprocessing by the deflecting-direction acquiring section 7, thedetecting section 8, the image analyzing section 9, thereference-position acquiring section 10, the light-reception-signalacquiring section 11, and the distance-information calculating section12 in the setting mode.

The coordinate calculating section 13 calculates a three-dimensionalcoordinate (Xb, Yb, Zb) of the irradiation position of the measurementlight on the measurement object S on the basis of the deflectingdirections of the deflecting sections 271 and 272 or the irradiationposition of the measurement light detected by the detecting section 8and the distance information calculated by the distance-informationcalculating section 12. The coordinate calculating section 13 maycalculate the three-dimensional coordinate (Xb, Yb, Zb) of theirradiation position of the measurement light on the measurement objectS on the basis of the plane coordinate indicating the irradiationposition on the measurement image of the measurement light detected bythe detecting section 8 and the distance information calculated by thedistance-information calculating section 12. The kinds or processing bythe determining section 14 and the height calculating section 15 in theheight gauge mode are respectively the same as the kinds of processingby the determining section 14 and the height calculating section 15 inthe setting mode.

(8) An Overall Flow of the Control System

FIGS. 14 to 17 are flowcharts for explaining an example of opticalscanning height measurement processing executed in theoptical-scanning-height measuring device 400 shown in FIG. 1. A seriesof processing explained below is executed at a fixed cycle by thecontrol section 310 and the control board 210 when a power supply of theoptical-scanning-height measuring device 400 is in an ON state. Notethat the optical scanning height measurement processing includesdesignation and measurement processing and actual measurement processingexplained below. In the following explanation, either one of thedesignation and measurement processing and the actual measurementprocessing in the optical scanning height measurement processing isexecuted by the control board 210. The other of the designation andmeasurement processing and the actual measurement processing in theoptical scanning height measurement processing is executed by thecontrol section 310. However, the present invention is not limited tothis. For example, both of the designation and measurement processingand the actual measurement processing in the optical scanning heightmeasurement processing may be executed by the control board 210 or thecontrol section 310.

In an initial state, it is assumed that the power supply of theoptical-scanning-height measuring device 400 is on in a state in whichthe measurement object S is placed on the optical surface plate 111shown in FIG. 2. At this point, the selection screen 341 shown in FIG.10 is displayed on the display section 340 shown in FIG. 1.

When the optical scanning height measurement processing is started, thecontrol section 310 determines whether the setting mode is selected byoperation of the operation section 330 by the user (step S101). Morespecifically, the control section 310 determines whether the settingbutton 341 a shown in FIG. 10 is operated by the user.

When the setting mode is not selected, the control section 310 proceedsto processing in step S201 in FIG. 17 explained below. On the otherhand, when the setting mode is selected, the control section 310 causesthe display section 340 shown in FIG. 1 to display a setting screen 350shown in FIG. 25 explained below (step S102). On the setting screen 350,a reference image of the measurement region V shown in FIG. 2 acquiredat a fixed cycle by the imaging section 220 is displayed on a real-timebasis.

In the optical-scanning-height measuring device 400 according to thisembodiment, in order to realize a correcting function of the correctingsection 17 shown in FIG. 12, it is necessary to set a pattern image anda search region in the setting mode. The pattern image means an image ofa portion including at least the measurement object S in an entireregion of a reference image displayed at a point in time designated bythe user. The search region means a range (a range in an imaging visualfield of the imaging section 220) in which, after the pattern image isset in the setting mode, a portion similar to the pattern image issearched in a measurement image in the measurement mode.

Thus, the control section 310 determines whether a search region isdesignated by the operation of the operation section 330 by the user(step S103). When a search region is not designated, the control section310 proceeds to processing in step S105 explained below. On the otherhand, when a search region is designated, the control section 310 setsthe designated search region by storing information concerning thedesignated search region in the storing section 320 (step S104).

Subsequently, the control section 310 determines whether a pattern imageis designated by the operation of the operation section 330 by the user(step S105). When a pattern image is not designated, the control section310 proceeds to processing in step S107 explained below. On the otherhand, when a pattern image is designated, the control section 310 setsthe designated pattern image by storing information concerning thedesignated pattern image in the storing section 320 (step S106). Notethat the information concerning the pattern image includes informationindicating a position of the pattern image in the reference image.Specific setting examples of the pattern image and the search region bythe user are explained below.

Subsequently, the control section 310 determines whether the searchregion and the pattern image are set by the processing in steps S104 andS105 (step S107). When at least one of the search region and the patternimage is not set, the control section 310 returns to the processing instep S103. On the other hand, when the search region and the patternimage are set, the control section 310 determines whether a settingcommand for a reference plane is received (step S108).

When the setting command for the reference plane is received in stepS108, the control section 310 determines whether designation of a pointserving as a reference point is received on the reference imagedisplayed on the display section 340 by the operation of the operationsection 330 by the user (step S109). When the designation of the pointis not received, the control section 310 proceeds to processing in thefollowing step S111. On the other hand, when the designation of thepoint is received, the control section 310 instructs the control board210 to perform the designation and measurement processing and gives aplane coordinate (Ua, Va) specified by the designated point on the imageto the control board 210 (see FIG. 11A). Consequently, the control board210 performs the designation and measurement processing (step S110) andgives a coordinate (Xc, Yc, Zc) specified by the designation andmeasurement processing to the control section 310. Details of thedesignation and measurement processing are explained below.

Thereafter, the control section 310 determines whether the designationof the point serving as the reference point is completed by theoperation of the operation section 330 by the user (step S111). When thedesignation of the point is not completed, the control section 310returns to the processing in step S109. On the other hand, when thedesignation of the point is completed, the control section 310 sets thereference plane on the basis of one or a plurality of coordinates (Xc,Yc, Zc) acquired in the designation and measurement processing in stepS110 (step S112). In this example, on the basis of coordinates (Xc, Yc,Zc) corresponding to one or a plurality of reference points, informationindicating coordinates of the reference plane, for example, planecoordinates (Xc, Yc) corresponding to the reference points orcoordinates (Xc, Yc, Zc) corresponding to the reference points arestored in the storing section 320.

The information indicating the coordinates of the reference plane mayinclude a reference plane constraint condition for determining thereference plane. The reference plane constraint condition includes acondition that, for example, the reference plane is parallel to aplacing surface or the reference plane is parallel to another surfacestored in advance. In the case of the reference plane constraintcondition, when a coordinate (Xb, Yb, Zb) corresponding to one referencepoint is designated, a plane represented by Z=Zb is acquired as thereference plane.

After the processing in step S112 or when the setting command for thereference plane is not received in step S108, the control section 310determines whether setting to be received is setting concerningmeasurement of the measurement object S (step S121). More specifically,the control section 310 determines whether the setting to be received issetting for specifying a portion of the measurement object S, the heightof which should be measured.

When the measurement to be received is not the setting concerningmeasurement, the control section 310 acquires information concerning thesetting by the operation of the operation section 330 by the user andstores the information in the storing section 320 (step S130). Examplesof the information acquired in step S130 include information such as theallowable value and an indicator and a comment that should be displayedon a measurement image during the measurement mode. Thereafter, thecontrol section 310 proceeds to processing in step S126 explained below.

When the setting received in step S121 is the setting concerning themeasurement, the control section 310 determines whether designation of apoint serving as a measurement point is received on the reference imagedisplayed on the display section 340 by the operation of the operationsection 330 by the user (step S122). When the designation of the pointis not received, the control section 310 proceeds to processing in thefollowing step S124. On the other hand, when the designation of thepoint is received, as in step S111 explained above, the control section310 instructs the control board 210 to perform the designation andmeasurement processing and gives a plane coordinate (Ua, Va) specifiedby the designated point on the image to the control board 210.Consequently, the control board 210 performs the designation andmeasurement processing (step S123) and gives a coordinate (Xc, Yc, Zc)specified by the designation and measurement processing to the controlsection 310.

Thereafter, the control section 310 determines whether the designationof the point serving as the measurement point is completed by theoperation of the operation section 330 by the user (step S124). When thedesignation of the point is not completed, the control section 310returns to the processing in step S122.

On the other hand, when the designation of the point is completed, thecontrol section 310 performs setting of the measurement point bystoring, in the storing section 320, coordinates (Xc, Yc, Zc) of one ora plurality of measurement points acquired in the designation andmeasurement processing in step S123 (step S125).

After the processing in either one of steps S125 and S130 explainedabove, the control section 310 determines whether completion of thesetting is instructed or new setting is instructed (step S126). When newsetting is instructed, that is, when the completion of the setting isnot instructed, the control section 310 returns to the processing instep S108.

On the other hand, when the completion of the setting is instructed, thecontrol section 310 registers, as registration information, the piecesof information set in any one of steps S103 to S112, S121 to S125, andS130 explained above in association with each other (step S127).Thereafter, the optical scanning height measurement processing ends inthe setting mode. A file of the registration information to beregistered is saved in the storing section 320 after a specific filename is attached to the file by the user. At this point, the informationtemporarily stored in the storing section 320 for setting in any one ofsteps S103 to S112, S121 to S125, and S130 may be erased.

In step S127, when the reference plane is set by the processing in stepS112 explained above, the control section 310 calculates height of themeasurement point on the basis of the reference plane and the specifiedcoordinate (Xc, Yc, Zc) and includes a result of the calculation in theregistration information. Note that, when the reference plane is alreadyset at a point in time of step S125 explained above, in step S125,height of the measurement point may be calculated on the basis of theset reference plane and the acquired coordinate (Xc, Yc, Zc). In thiscase, a result of the calculation may be displayed on the setting screen350 (FIG. 29) as the height of the measurement point.

When the setting mode is not selected in step S101 explained above, thecontrol section 310 determines whether the measurement mode is selectedby the operation of the operation section 330 by the user (step S201).More specifically, the control section 310 determines whether themeasurement button 341 b shown in FIG. 10 is operated by the user. Whenthe measurement mode is selected, the control section 310 causes thedisplay section 340 shown in FIG. 1 to display a measurement screen 360shown in FIG. 34 (step S202). On the measurement screen 360, ameasurement image in the measurement region V shown in FIG. 2 acquiredat a fixed cycle by the imaging section 220 is displayed on a real-timebasis.

Subsequently, the control section 310 determines whether a file of theregistration information is designated by the operation of the operationsection 330 by the user (step S203). Specifically, the control section310 determines whether a filename of the registration information isdesignated by the user. When a file is not designated, the controlsection 310 stays on standby until designation of a file is received. Onthe other hand, when receiving designation of a file, the controlsection 310 reads the designated file of the registration informationfrom the storing section 320 (step S204). Note that, when the designatedfile of the registration information is not stored in the storingsection 320, the control section 310 may display, on the display section340, information indicating that the designated file is absent.

Subsequently, the control section 310 acquires registered informationconcerning a pattern image from the read registration information andsuperimposes and displays the acquired pattern image on the measurementimage displayed on the display section 340 (step S205). At this point,the control section 310 acquires a search region in addition to thepattern image. Note that, as explained above, the information concerningthe pattern image also includes information indicating a position of thepattern image in the reference image. Therefore, the pattern image issuperimposed and displayed on the measurement image in the same positionas the position set in the setting mode.

The pattern image may be displayed semitransparent. In this case, theuser can easily compare a currently captured measurement image of themeasurement object S and the reference image of the measurement object Sacquired during the setting mode. Then, the user can perform work forpositioning the measurement object S on the optical surface plate 111.

Subsequently, the control section 310 performs comparison of the patternimage and the measurement image (step S206). Specifically, the controlsection 310 extracts, as a reference edge, an edge of the measurementobject S in the pattern image and searches whether an edge having ashape corresponding to the reference edge is present in the acquiredsearch region.

In this case, an edge portion of the measurement object S in themeasurement image is considered to be most similar to the referenceedge. When a portion of the measurement image most similar to thereference edge is detected, the control section 310 calculates how muchthe detected portion deviates from the reference edge on the image andcalculates how Much the detected portion rotates from the reference edgeon the image (step S207).

Subsequently, the control section 310 acquires information concerning aregistered measurement point from the read registration information andcorrects the acquired information concerning the measurement point onthe basis of a calculated deviation amount and a calculated rotationamount (step S208). The processing in steps S206 to S208 is equivalentto the function of the correcting section 17 shown in FIG. 12. With thisconfiguration, even when a measurement object in a corrected image isdisplaced or rotated with respect to the measurement object in thepattern image, it is possible to highly accurately and easily specifyand correct a measurement point.

Subsequently, the control section 310 instructs the control board 210 toperform the actual measurement processing for each of correctedmeasurement points and gives a coordinate (Xc, Yc, Zc) of the correctedmeasurement point to the control board 210 (see FIG. 11B). Consequently,the control board 210 performs the actual measurement processing (stepS209) and gives a coordinate (Xb, Yb, Zb) specified by the actualmeasurement processing to the control section 310. Details of the actualmeasurement processing are explained below.

Subsequently, the control section 310 acquires registered informationconcerning a reference plane, calculates height of a measurement pointon the basis of the reference plane and the acquired coordinate (Xb, Yb,Zb), and stores a result of the calculation in the storing section 320as a measurement result. The control section 310 performs various kindsof processing corresponding to registered other kinds of information(step S210). As the various kinds of information corresponding to theregistered other kinds of information, for example, when an allowablevalue is included in read registration information, inspectionprocessing for determining whether the calculation result of the heightis within a range of a tolerance set by the allowable value may beperformed. Thereafter, the optical scanning height measurementprocessing ends in the measurement mode.

When the measurement mode is not selected in step S201 explained above,the control section 310 determines whether the height gauge mode isselected by the operation of the operation section 330 by the user (stepS211). More specifically, the control section 310 determines whether theheight gauge button 341 c shown in FIG. 10 is operated by the user. Whenthe height gauge mode is not selected, the control section 310 returnsto the processing in step S101.

On the other hand, when the height gauge mode is selected, the controlsection 310 causes the display section 340 shown in FIG. 1 to displaythe setting screen 350 shown in FIG. 27 explained below (step S212).Thereafter, the control section 310 performs setting of a referenceplane on the basis of the operation of the operation section 330 by theuser (step S213). This setting processing is the same as the processingin steps S109 to S112 explained above.

Thereafter, when designation of a point is received, the control section310 instructs the control board 210 to perform the designation andmeasurement processing and gives a plane coordinate (Ua, Va) specifiedby the designated point on the image to the control board 210 (see FIG.11C). Consequently, the control board 210 performs the designation andmeasurement processing (step S214). The control board 210 adjusts thepositions of the movable sections 252 a and 252 b shown in FIG. 5 andthe angles of the reflecting sections 271 b and 272 b shown in FIG. 7 onthe basis of the coordinate (Xc, Yc, Zc) specified by the designationand measurement processing and the position conversion information andirradiates measurement light (step S215).

Subsequently, the control board 210 calculates, on the basis of thelight reception signal output from the light receiving section 232 dshown in FIG. 4, the positions of the movable sections 252 a and 252 bshown in FIG. 5, and the deflecting directions of the deflectingsections 271 and 272 shown in FIG. 7, a three-dimensional coordinate(Xb, Yb, Zb) of a portion on which the measurement light is irradiatedon the measurement object S and gives the three-dimensional coordinate(Xb, Yb, Zb) to the control section 310 (step S216).

Note that, in step S216 explained above, the control board 210 maycalculate; on the basis of the light reception signal output from thelight receiving section 232 d shown in FIG. 4, the positions of themovable sections 252 a and 252 b shown in FIG. 5, and the planecoordinate indicating the irradiation position of the measurement lighton the image acquired by the imaging section 220 shown in FIG. 1, thethree-dimensional coordinate (Xb, Yb, Zb) of the portion on which themeasurement light is irradiated on the measurement object S.

Subsequently, the control section 310 acquires information concerningthe set reference plane, calculates, on the basis of the reference planeand the acquired coordinate (Xb, Yb, Zb), height of the portion on whichthe measurement light is irradiated on the measurement object S, anddisplays a result of the calculation on the display section 340 as ameasurement result. For example, when the reference plane is a plane,the control section 310 calculates, as height, the length of aperpendicular of the reference plane, which passes the acquiredcoordinate (Xb, Yb, Zb), from the reference plane to the coordinate (Xb,Yb, Zb) at the time when the perpendicular is drawn and displays aresult of the calculation on the display section 340 as a measurementresult. The control section 310 displays, on the display section 340, agreen “+” mark, which indicates that the height of the portion of themeasurement object S corresponding to the measurement point can becalculated, in a plane coordinate indicating the irradiation position ofthe measurement light on the image acquired by the imaging section 220or a plane coordinate specified by the point designated on the image(step S217).

Subsequently, the control section 310 determines whether an additionalpoint is designated by the operation of the operation section 330 by theuser (step S218). When an additional point is designated, the controlsection 310 returns to the processing in step S214. Consequently, theprocessing in steps S214 to S218 is repeated until no additional pointis designated. When an additional point is not designated, the opticalscanning height measurement processing ends in the height gauge mode.

With the height gauge mode explained above, the user can designate areference point and a reference plane by designating a point on animage. The user can acquire a measurement result of height bydesignating a measurement point on a screen. Further, the user cancontinue the measurement while continuously maintaining the referenceplane by designating a plurality of measurement points.

(9) An Example of the Designation and Measurement Processing

FIGS. 18 and 19 are flowcharts for explaining an example of thedesignation and measurement processing by the control board 210. FIGS.20 and 21 are explanatory diagrams for explaining the designation andmeasurement processing shown in FIGS. 18 and 19. In each of FIGS. 20A,20B, and 20C and FIGS. 21A and 21B, on the left side, a positionalrelation between the measurement object S placed on the optical surfaceplate 111 and the imaging section 220 and the scanning section 270 isshown as a side view and, on the right side, an image displayed on thedisplay section 340 by imaging of the imaging section 220 is shown. Theimage displayed on the display section 340 includes an image SI of themeasurement object S. In the following explanation, a plane coordinateon the image displayed on the display section 340 is referred to asscreen coordinate.

The control board 210 starts the designation and measurement processingby receiving a command for the designation and measurement processingfrom the control section 310. Therefore, the control board 210 acquiresa screen coordinate (Ua, Va) given from the control section 310 togetherwith the command (step S301).

On the right side of FIG. 20A, the screen coordinate (Ua, Va) is shownon the image displayed on the display section 340. n the left side ofFIG. 20A, a portion of the measurement object S corresponding to thescreen coordinate (Ua, Va) is indicated by a point P0.

In step S301, a component of the Z axis (a component in the heightdirection) in a coordinate of the point P0 corresponding to the screencoordinate (Ua, Va) is unknown. Therefore, the control board 210 assumesthe component of the Z axis of the point P0 designated by the user as“Za” (step S302). In this case, as shown in FIG. 20B, the assumedcomponent of the Z axis does not always coincide with a component of theZ axis of an actually designated point P0.

Subsequently, the control board 210 calculates, on the basis of thecoordinate conversion information explained above, a plane coordinate(Xa, Ya) corresponding to the screen coordinate (Ua, Va) at the timewhen the component of the Z axis is the assumed “Za” (step S303).Consequently, as shown in FIG. 20B, a coordinate (Xa, Ya, Za) of animaginary point P1 corresponding to the screen coordinate (Ua, Va) andthe assumed component of the Z axis is obtained. Note that, in thisexample, it is assumed that “Za” is an intermediate position in the Zdirection in the measurement region V shown in FIG. 2.

Subsequently, the control board 210 adjusts the positions of the movablesections 252 a and 252 b shown in FIG. 5 and the angles of thereflecting sections 271 b and 272 b shown in FIG. 7 on the basis of thecoordinate (Xa, Ya, Za) obtained by processing in step S303 and theposition conversion information and irradiates the measurement light(step S304).

In this case, when the component of the Z axis assumed in step S302greatly deviates from a component of the Z axis of the actuallydesignated point P0, as shown in the side view on the left side of FIG.20C, an irradiation position of the measurement light on the measurementobject S greatly deviates from the actually designated point P0.Therefore, processing explained below is performed.

According to processing in step S304, an irradiation portion (a lightspot) of the measurement light irradiated on the measurement object Sfrom the scanning section 270 appears on the image acquired by theimaging section 220. In this case, it is possible to easily detect ascreen coordinate of the irradiation portion of the measurement lightusing image processing and the like. In the figure on the right side ofFIG. 20C, an irradiation portion (a light spot) of the measurement lightappearing on an image displayed on the display section 340 is indicatedby a circle.

After the processing in step S304, the control board 210 detects, as ascreen coordinate (Uc, Vc), a plane coordinate indicating an irradiationposition of the measurement light on the image acquired by the imagingsection 220 and detects a deflecting direction of the measurement lightfrom the angles of the reflecting sections 271 b and 272 b shown in FIG.7 (step S305).

Subsequently, the control board 210 sets, as a coordinate (Xc, Yc, Zc),a coordinate of an irradiation position P2 of the measurement light onthe measurement object S or the optical surface plate 111 on the basisof the detected screen coordinate (Uc, Vc) and the deflecting direction(step S306).

As shown in FIG. 20C, when the irradiation position P2 deviates from thepoint P0, the screen coordinate (Uc, Vc) deviates from the screencoordinate (Ua, Va). Therefore, the control board 210 calculates anerror (Ua-Uc, Va-Vc) of the detected screen coordinate (Uc, Vc) withrespect to the screen coordinate (Ua, Va) and determines whether thecalculated error is within a determination range decided in advance(step S307). The determination range used at this point may be able tobe set by the user or may be set in advance during factory shipment ofthe optical-scanning-height measuring device 400.

When, in step S307, the error (Ua-Uc, Va-Vc) is within the determinationrange decided in advance, the control board 210 specifies, as acoordinate designated by the user, the coordinate (Xc, Yc, Zc) decidedin the immediately preceding step S306 (step S308) and ends thedesignation and measurement processing. Thereafter, the control board210 gives the specified coordinate (Xc, Yc, Zc) to the control section310.

When, in step S307, the error (Ua-Uc, Va-Vc) is outside thedetermination range decided in advance, the control board 210 adjuststhe deflecting direction of the measurement light on the basis of theerror (Ua-Uc, Va-Vc) (step S309). Specifically, for example, a relationbetween errors on screen coordinates corresponding to the X axis and theY axis and angles of the reflecting sections 217 b and 272 b that shouldbe adjusted is stored in the storing section 320 in advance as an errorcorrespondence relation. Then, as indicated by a white arrow in FIG.21A, the control board 210 finely adjusts the deflecting direction ofthe measurement light on the basis of the calculated error (Ua-Uc,Va-Vc) and the error correspondence relation.

Thereafter, the control board 210 returns to the processing in stepS305. Consequently, after the deflecting direction of the measurementlight is finely adjusted, the processing in steps S305 to S307 isperformed again. As a result, finally, as shown in FIG. 21B, the error(Ua-Uc, Va-Vc) is within the determination range. Consequently, acoordinate (Xc, Yc, Zc) corresponding to the measurement pointdesignated by the user is specified.

In this example, the coordinate of the irradiation position P2 iscalculated as the coordinate (Xc, Yc, Zc) by the processing in stepS306. However, the present invention is not limited to this. Thecoordinate of the irradiation position P2 may be calculated as thecoordinate (Xc, Yc, Zc) by processing in steps S405 and S406 in thedesignation and measurement processing shown in FIGS. 22 and 23explained below.

(10) Another Example of the Designation and Measurement Processing

FIGS. 22 and 23 are flowcharts for explaining another example of thedesignation and measurement processing by the control board 210. FIGS.24A and 24B are explanatory diagrams for explaining the designation andmeasurement processing shown in FIGS. 22 and 23. In each of FIGS. 24Aand 24B, on the left side, a positional relation between the measurementobject S placed on the optical surface plate 111 and the imaging section220 and the scanning section 270 is shown as a side view and, on theright side, an image displayed on the display section 340 by imaging ofthe imaging section 220 is shown.

When the designation and measurement processing is started, the controlboard 210 acquires a screen coordinate (Ua, Va) given from the controlsection 310 together with a command (step S401). Subsequently, as in theprocessing in step S302 explained above, the control board 210 assumes acomponent of the Z axis of the point P0 designated by the user as “Za”(step S402). In this case, as in the example shown in FIG. 20B, theassumed component of the Z axis does not always coincide with acomponent of the Z axis of an actually designated point P0.

Subsequently, as in the processing in step S303 explained above, thecontrol board 210 calculates a plane coordinate (Xa, Ya) correspondingto a screen coordinate (Ua, Va) at the time when the assumed componentof the Z axis is “Za” (step S403). As in the processing in step S304explained above, the control board 210 adjusts the positions of themovable sections 252 a and 252 b shown in FIG. 5 and the angles of thereflecting sections 271 b and 272 b shown in FIG. 7 on the basis of acoordinate (Xa, Ya, Za) of the imaginary point P1 obtained by theprocessing in step S403 and the position conversion information andirradiates the measurement light (step S404). In step S404, a relationbetween the point P0 designated by the user and the irradiation positionof the measurement light irradiated on the measurement object S is thesame as the state shown in FIG. 20C explained above. Thereafter, thefollowing processing is performed such that the irradiation position ofthe measurement light on the measurement object S coincides with or isclose to the actually designated point P0.

First, the control board 210 detects the positions of the movablesections 252 a and 252 b shown in FIG. 5 and detects a deflectingdirection of the measurement light from the angles of the reflectingsections 271 b and 272 b shown in FIG. 7 (step S405).

Subsequently, the control board 210 calculates a distance between theemitting position of the measurement light (the position of the port 245d of the light guide section 240) and the irradiation position of themeasurement light in the measurement object S on the basis of thepositions of the movable sections 252 a and 252 b detected in theimmediately preceding step S405 and the light reception signal acquiredby the light receiving section 232 d shown in FIG. 4. The control board210 sets, as a coordinate (Xc, Yc, Zc), a coordinate of the irradiationposition P2 of the measurement light on the measurement object S or theoptical surface plate 111 on the basis of the calculated distance andthe deflecting direction of the measurement light detected in theimmediately preceding step S405 (step S406).

According to the processing in step S406 explained above, it isestimated that the component “Zc” of the Z axis of the irradiationposition P2 of the measurement light is a value coinciding with or closeto the component of the Z axis of the point P0 designated by the user.Therefore, the control board 210 calculates, on the basis of thecoordinate conversion information, a plane coordinate (Xa′, Ya′)corresponding to a screen coordinate (Ua, Va) at the time when thecomponent of the Z axis is the assumed “Zc” (step S407). Consequently,as shown in FIG. 24A, a coordinate (Xa′, Ya′, Zc) of an imaginary pointP3 corresponding to the screen coordinate (Ua, Va) and the assumedcomponent of the Z axis is obtained.

Subsequently, the control board 210 calculates an error (Xa′-Xc, Ya′-Yc)of the plane coordinate (Xc, Yc) of the irradiation position P2 withrespect to the plane coordinate (Xa′, Ya′) of the imaginary point P3 anddetermines whether the calculated error is within a determination rangedecided in advance (step S408). The determination range used at thispoint may be able to be set by the user or may be set in advance duringfactory shipment of the optical-scanning-height measuring device 400.

When, in step S408, the error (Xa′-Xc, Ya′-Yc) is within thedetermination range decided in advance, the control board 210 specifies,as a coordinate designated by the user, the coordinate (Xc, Yc, Zc) ofthe irradiation position P2 decided in the immediately preceding stepS406 (step S409) and ends the designation and measurement processing.Thereafter, the control board 210 gives the specified coordinate (Xc,Yc, Zc) to the control section 310.

When, in step S408, the error (Xa′-Xc, Ya′-Yc) is outside thedetermination range decided in advance, the control board 210 sets, asthe coordinate (Xa, Ya, Za) set as an irradiation target of themeasurement light in step S404 explained above, the coordinate (Xa′,Ya′, Za′) of the imaginary point P3 obtained in the immediatelypreceding step S407 (step S410). Thereafter, the control board 210returns to the processing in step S404.

Consequently, after the deflecting direction of the measurement light ischanged, the processing in steps S404 to S408 is performed again. As aresult, finally, as shown in FIG. 24B, since the error (Xa′-Xc, Ya′-Yc)is within the determination range, a coordinate (Xc, Yc, Zc)corresponding to the measurement point designated by the user isspecified.

In this example, the coordinate of the irradiation position P2 iscalculated as the coordinate (Xc, Yc, Zc) by the processing in stepsS405 and S406. However, the present invention is not limited to this.The coordinate of the irradiation position P2 may be calculated as thecoordinate (Xc, Yc, Zc) by processing in step S306 in the designationand measurement processing shown in FIGS. 18 and 19.

(11) The Actual Measurement Processing

The control board 210 receives a command for the actual measurementprocessing from the control section 310 to thereby start the actualmeasurement processing. When the actual measurement processing isstarted, first, the control board 210 acquires a coordinate (Xc, Yc, Zc)of the measurement point given from the control section 310 togetherwith the command.

Even if the measurement light is irradiated on the basis of thecoordinate (Xc, Yc, Zc) of the measurement point set in the setting modeand the position conversion information, a plane coordinate of anirradiation position of the measurement light on the measurement objectS greatly deviates from the coordinate of the measurement pointdepending on a shape of the measurement object S measured in themeasurement mode.

For example, when a component of the Z axis of the portion of themeasurement object S corresponding to the measurement point greatlydeviates from “Zc”, the plane coordinate of the irradiation position ofthe measurement light greatly deviates from the set plane coordinate(Xc, Yc) of the measurement point. Therefore, in the actual measurementprocessing, the plane coordinate of the irradiation position of themeasurement light is adjusted to fit within a fixed range from the planecoordinate (Xc, Yc) of the measurement point.

Specifically, for example, after setting a screen coordinatecorresponding to the acquired coordinate (Xc, Yc, Zc) of the measurementpoint as (Ua, Va), the control board 210 sets the acquired coordinate(Xc, Yc, Zc) of the measurement point as the coordinate (Xa, Ya, Za) ofthe imaginary point P1 obtained in the processing in step S303 in FIG.18. Subsequently, the control board 210 performs processing in stepsS304 to S308 shown in FIGS. 18 and 19. Subsequently, the control board210 adjusts the positions of the movable sections 252 a and 252 b shownin FIG. 5 and the angles of the reflecting sections 271 b and 272 bshown in FIG. 7 on the basis of the coordinate (Xc, Yc, Zc) specified inthe processing in step S308 and the position conversion information andirradiates the measurement light.

Thereafter, the control board 210 calculates, on the basis of the lightreception signal output from the light receiving section 232 d shown inFIG. 4, the positions of the movable sections 252 a and 252 b shown inFIG. 5, and the deflecting directions of the deflecting sections 271 and272 shown in FIG. 7, a three-dimensional coordinate (Xb, Yb, Zb) of aportion on which the measurement light is irradiated on the measurementobject S and gives the three-dimensional coordinate (Xb, Yb, Zb) to thecontrol section 310. Consequently, the actual measurement processingends. Note that the control board 210 may calculate, on the basis of thelight reception signal output from the light receiving section 232 dshown in FIG. 4, the positions of the movable sections 252 a and 252 bshown in FIG. 5, and the plane coordinate indicating the irradiationposition of the measurement light on the image acquired by the imagingsection 220 shown in FIG. 1, the three-dimensional coordinate (Xb, Yb,Zb) of the portion on which the measurement light is irradiated on themeasurement object S.

Alternatively, the control board 210 may execute the actual measurementprocessing as explained below. For example, after setting a screencoordinate corresponding to the acquired coordinate (Xc, Yc, Zc) of themeasurement point to (Ua, Va), the control board 210 sets the acquiredcoordinate (Xc, Yc, Zc) of the measurement point as the coordinate (Xa,Ya, Za) of the imaginary point P1 obtained in the processing in stepS403 in FIG. 22. Subsequently, the control board 210 performs processingin steps S404 to S409 shown in FIGS. 22 and 23. Subsequently, thecontrol board 210 adjusts the positions of the movable sections 252 aand 252 b shown in FIG. 5 and the angles of the reflecting sections 271b and 272 b shown in FIG. 7 on the basis of the coordinate (Xc, Yc, Zc)specified in the processing in step S408 and the position conversioninformation and irradiates the measurement light.

Thereafter, as in the example explained above, the control board 210calculates, on the basis of the light reception signal output from thelight receiving section 232 d shown in FIG. 4, the positions of themovable sections 252 a and 252 b shown in FIG. 5, and the deflectingdirections of the deflecting sections 271 and 272 shown in FIG. 7, athree-dimensional coordinate (Xb, Yb, Zb) of the portion on which themeasurement light is irradiated on the measurement object S and givesthe three-dimensional coordinate (Xb, Yb, Zb) to the control section310. Alternatively, the control board 210 calculates, on the basis ofthe light reception signal output from the light receiving section 232 dshown in FIG. 4, the positions of the movable sections 252 a and 252 bshown in FIG. 5, and the plane coordinate indicating the irradiationposition of the measurement light on the image acquired by the imagingsection 220 shown in FIG. 1, the three-dimensional coordinate (Xb, Yb,Zb) of the portion on which the measurement light is irradiated on themeasurement object S and gives the three-dimensional coordinate (Xb, Yb,Zb) to the control section 310.

(12) An Operation Example in which the Setting Mode and the MeasurementMode are Used

FIGS. 25 to 30 are diagrams for explaining an operation example of theoptical-scanning-height measuring device 400 in the setting mode. In thefollowing explanation, the users of the optical-scanning-heightmeasuring device 400 are distinguished as the measurement manager andthe measurement operator and explained.

First, the measurement manager positions the measurement object S, whichserves as a reference of height measurement, on the optical surfaceplate 111 and operates the setting button 341 a shown in FIG. 10 usingthe operation section 330 shown in FIG. 1. Consequently, theoptical-scanning-height measuring device 400 starts the operation in thesetting mode. In this case, for example, as shown in FIG. 25, thesetting screen 350 is displayed on the display section 340 shown inFIG. 1. The setting screen 350 includes an image display region 351 anda button display region 352. In the image display region 351, acurrently captured image of the measurement object S is displayed in theimage display region 351 as a reference image RI. In the diagrams ofFIGS. 25 to 30 and the diagrams of FIGS. 31 to 36 referred to below, acontour indicating a shape of the measurement object S in the referenceimage RI and a measurement image MI explained below displayed in theimage display region 351 is indicated by a thick solid line.

At a start point in time of the setting mode, in the button displayregion 352, a search region button 352 a, a pattern image button 352 b,and a setting completion button 352 c are displayed. The measurementmanager operates, for example, the search region button 352 a to performdrag operation or the like on the image display region 351.Consequently, the measurement manager sets a search region SR asindicated by a dotted line in FIG. 25. The measurement manager operates,for example, the pattern image button 352 b to perform the dragoperation or the like on the image display region 351. Consequently, itis possible to set a pattern image PI as indicated by an alternate longand short dash line in FIG. 25.

After setting the search region SR and the pattern image PI, themeasurement manager operates the setting completion button 352 c.Consequently, the setting of the search region SR and the pattern imagePI is completed. A display form of the setting screen 350 is switched asshown in FIG. 26. Specifically, in the image display region 351,indicators indicating the set search region SR and the set pattern imagePI are removed. In the button display region 352, a point designationbutton 352 d and a reference plane setting button 352 e are displayedinstead of the search region button 352 a and the pattern image button352 b shown in FIG. 25.

The measurement manager operates the point designation button 352 d toperform, for example, click operation on the image display region 351.Consequently, one or a plurality of (in this example, three) referencepoints are designated as indicated by “+” marks in FIG. 27. Thereafter,the measurement manager operates the reference plane setting button 352e. Consequently, a reference plane including the designated one orplurality of reference points is set. As indicated by an alternate longand two short dashes line in FIG. 28, an indicator indicating areference plane RF set in the image display region 351 is displayed.When four or more reference points are designated, all of the four ormore reference points are not always included in the reference plane RF.In this case, the reference plane RF is set such that, for example,distances among the plurality of reference points are small as a whole.Similarly, when a reference plane constraint condition for determining areference plane is decided, for example, when a condition that, forexample, the reference plane is parallel to a placing surface or thereference plane is parallel to other surfaces stored in advance, isdecided, when two or more reference points are designated, all of thetwo or more reference points do not always need to be included in thereference plane RF. Note that a plurality of reference planes RF may beset by repeating the operation of the point designation button 352 d andthe reference plane setting button 352 e.

Thereafter, the measurement manager operates the setting completionbutton 352 c. Consequently, the setting of the reference plane RF iscompleted. A display form of the setting screen 350 is switched as shownin FIG. 29. Specifically, in the image display region 351, theindicators indicating the one or plurality of reference points used forthe setting of the reference plane RF are removed. In the button displayregion 352, an allowable value button 352 g is displayed instead of thereference plane setting button 352 e shown in FIG. 28.

The measurement manager operates the point designation button 352 d toperform, for example, click operation on the image display region 351.Consequently, as indicated by “+” marks in FIG. 30, measurement pointsare designated. When a plurality of reference planes RF are set, onereference plane RF is selected out of the plurality of reference planesRF set as the reference plane RF serving as a reference for designatedmeasurement points. When the designation and measurement processingexplained above is performed concerning the designated measurementpoints and heights of portions of the measurement object S correspondingto the measurement points can be calculated, the heights of the portionsof the measurement object S corresponding to the measurement points aredisplayed on the image display region 351. At this point, a color of the“+” marks may be changed to, for example, green to indicate that theheights of the portions of the measurement object S corresponding to themeasurement points can be calculated.

On the other hand, when the designation and measurement processingexplained above is performed concerning the designated measurementpoints and the heights of the portions of the measurement object Scorresponding to the measurement points cannot be calculated, an errormessage such as “FAIL” may be displayed on the image display region 351.Further, the color of the “+” marks may be changed to, for example, redto indicate that the heights of the portions of the measurement object Scorresponding to the measurement points cannot be calculated.

When a plurality of measurement points are designated, it may bepossible to designate measurement route information. It may be possibleto set information indicating that, for example, a measurement route isset in the order of the designation of the plurality of measurementpoints or a measurement route is set to be the shortest.

During the designation of the measurement points, by further operatingthe allowable value button 352 g, the measurement manager can set adesign value and a tolerance as allowable values for each of themeasurement points. Lastly, the measurement manager operates the settingcompletion button 352 c. Consequently, a series of information includingthe reference plane RF, the plurality of measurement points, and theallowable values are stored in the storing section 320 as registrationinformation in association with one another. At this point, a specificfile name is given to the registration information. Note that the filename may be capable of being set by the measurement manager.

As shown in FIGS. 27 to 30, indicators “+” indicating the positions ofthe reference points and the measurement points designated by themeasurement manger are superimposed and displayed on the reference imageRI. Consequently, the measurement manager can easily confirm thedesignated reference points and the designated measurement points byvisually recognizing the indicators superimposed and displayed on thereference image RI of the measurement object S.

In the present invention, the order of the setting of reference pointsand measurement points in the setting mode is not limited to the exampleexplained above. The setting of reference points and measurement pointsmay be performed as explained below.

FIGS. 31 to 33 are diagrams for explaining another operation example ofthe optical-scanning-height measuring device 400 in the setting mode. Inthis example, after the setting of the search region SR and the patternimage PI, as shown in FIG. 31, the setting completion button 352 c, thepoint designation button 352 d, the reference plane setting button 352e, the allowable value button 352 g, a reference point setting button352 h, and a measurement point setting button 352 i are displayed in thebutton display region 352.

In this state, the measurement manger operates the point designationbutton 352 d to perform click operation or the like on the image displayregion 351. At this point, as indicated by the “+” marks in FIG. 27, themeasurement manager designates a plurality of (in this example, five)points that can be reference points or measurement points.

Subsequently, the measurement manager operates the reference pointsetting button 352 h or the measurement point setting button 352 i foreach of the designated points to thereby determine whether the point isused as a reference point or used as a measurement point. Further, afterdetermining one or a plurality of points as reference points, themeasurement manager operates the reference plane setting button 352 e.Consequently, as shown in FIG. 32, one or a plurality of (in thisexample, three) reference points are displayed in the image displayregion 351 as indicated by dotted line “+” marks. A reference planebased on the one or plurality of reference points is displayed asindicated by an alternate long and two short dashes line. Further, oneor a plurality of (in this example, two) measurement points aredisplayed as indicated by solid line “+” marks.

Thereafter, as shown in FIG. 33, heights of portions of the measurementobject S corresponding to the designated measurement points aredisplayed on the image display region 351. At this point, as in theexample explained above, the measurement manager can set design valuesand tolerances as allowable values for each of the measurement points byoperating the allowable value button 352 g. Lastly, the measurementmanager operates the setting completion button 352 c.

FIGS. 34 to 36 are diagrams for explaining an operation example of theoptical-scanning-height measuring device 400 in the measurement mode.The measurement operator positions the measurement object S set as atarget of height measurement on the optical surface plate 111 andoperates the measurement button 341 b shown in FIG. 10 using theoperation section 330 shown in FIG. 1. Consequently, theoptical-scanning-height measuring device 400 starts the operation in themeasurement mode. In this case, for example, as shown in FIG. 34, themeasurement screen 360 is displayed on the display section 340 shown inFIG. 1. The measurement screen 360 includes an image display region 361and a button display region 362. In the image display region 361, acurrently captured image of the measurement object S is displayed as themeasurement image MI.

At a start point in time of the measurement mode, a file reading button362 a is displayed in the button display region 362. The measurementoperator selects a file name pointed by the measurement manager byoperating the file reading button 362 a. Consequently, registrationinformation of height measurement corresponding to the measurementobject S placed on the optical surface plate 111 is read.

When the registration information is read, as shown in FIG. 35, thepattern image PI corresponding to the read registration information issuperimposed and displayed on the measurement image MI of the imagedisplay region 361 in a semitransparent state. A measurement button 362b is displayed in the button display region 362. In this case, themeasurement operator can position the measurement object S in a moreappropriate position on the optical surface plate 111 while referring tothe pattern image PI.

Thereafter, the measurement operator operates the measurement button 362b after performing the more accurate positioning work for themeasurement object S. Consequently, heights from a reference plane of aplurality of portions of the measurement object S corresponding to aplurality of measurement points of the read registration information aremeasured. When an allowable value is included in the read registrationinformation, pass/fail determination of the portions corresponding tothe measurement points is performed on the basis of the allowable value.

As a result, as shown in FIG. 36, the heights of the portions of themeasurement object S respectively corresponding to the set measurementpoints are displayed on the image display region 361. The heights of theportions of the measurement object S respectively corresponding to theset measurement points are displayed on the button display region 362. Aresult of the pass/fail determination based on the allowable value isdisplayed as an inspection result.

(13) Effects

(a) In the optical-scanning-height measuring device 400 according tothis embodiment, the measurement point is designated by the user,whereby the light emitted from the light emitting section 231 isdeflected by the deflecting sections 271 and 272. Consequently, thelight is sequentially irradiated on the plurality of portions P in thepartial region PA including or surrounding the portion of themeasurement object S corresponding to the measurement point. At thispoint, the deflecting directions of the deflecting sections 271 and 272corresponding to the partial region PA or the irradiation position ofthe measurement light corresponding to the partial region PA is detectedby the detecting section 8.

The measurement light from the measurement object S is received by thelight receiving section 232 d and the light reception signal indicatingthe received light amount is output. The height of the portion of themeasurement object S corresponding to the measurement point iscalculated by the height calculating section 15 on the basis of thedeflecting directions of the deflecting sections 271 and 272 or theirradiation position of the measurement light detected by the detectingsection 8 and integration data concerning the light reception signalobtained according to the incidence of the light on the light receivingsection 232 d from the plurality of portions P in the partial region PA.

As explained above, the light emitted from the light emitting section231 and deflected by the deflecting sections 271 and 272 is irradiatedon the plurality of portions P in the partial region PA of themeasurement object S. Consequently, the light is reflected from at leasta part of the plurality of portions P to the light receiving section 232d, whereby, irrespective of the direction of the light and the surfacestate of the measurement object S, it is possible to acquire, atsufficient strength, the light reception signal output from the lightreceiving section 232 d. Therefore, it is possible to calculate theheight of the portion of the measurement object S corresponding to themeasurement point on the basis of the acquired light reception signal.As a result, it is possible to reduce the unmeasurable region on thesurface of the measurement object S.

(b) In this embodiment, the deflecting sections 271 and 272 arecontrolled by the control board 210 to irradiate the measurement lighton the plurality of portions P in the partial region PA. In this case, acomponent that guides the light to the plurality of portions P in thepartial region PA is unnecessary other than the deflecting sections 271and 272. Therefore, the configuration of the optical-scanning-heightmeasuring device 400 is simplified.

(c) In the optical-scanning-height measuring device 400 according tothis embodiment, the user can designate the measurement point on thereference image of the measurement object S. Height of a portion of themeasurement object S corresponding to the measurement point designatedon the reference image is automatically calculated. Therefore, even whenthe user is not skilled, by designating a desired portion of themeasurement object S on an image, it is possible to uniformly acquire acalculation result of height of the portion.

For example, a skilled measurement manager designates a measurementpoint on the reference image of the measurement object S in the settingmode. Consequently, in the measurement mode, even when the measurementoperator is not skilled, it is possible to uniformly acquire acalculation result of height of a corresponding portion of themeasurement object S. Consequently, it is possible to accurately andeasily measure a shape of the desired portion of the measurement objectS.

(d) When the position-information acquiring section 2 receives thedesignation of the measurement point a plurality of times, every timethe designation of the measurement point is received, the measurementlight is irradiated on the portion of the measurement object Scorresponding to the measurement point and the height of the portion iscalculated. The calculation of the height can be executed before theposition-information acquiring section 2 receives designation of thenext measurement point. Consequently, it is possible to quickly acquireheights of a plurality of portions of the measurement object S.

(14) Other Embodiments

(a) In the embodiment explained above, the control board 210 controlsthe deflecting sections 271 and 272 of the scanning section 270 in orderto irradiate the measurement light on the plurality of portions P of thepartial region PA corresponding to the measurement point. However, thepresent invention is not limited to this. The optical-scanning-heightmeasuring device 400 may include a shift mechanism explained below inorder to irradiate the measurement light on the plurality of portions Pof the partial region PA corresponding to the measurement point.

FIG. 37 is a schematic diagram showing the configuration of a part ofthe measurement head 200 according to another embodiment. In FIG. 37, aconfiguration is shown in which the shift mechanism 290 is providedbetween the focusing section 260 and the scanning section 270 in themeasurement head 200.

As shown in FIG. 37, the shift mechanism 290 is provided on an opticalpath of the measurement light MB between the focusing section 260 andthe scanning section 270 and includes a flat member 291 and a drivingsection 292. The flat member 291 is formed by a tabular member havingtransmittance. The flat member 291 may be, for example, flat glass, maybe a lens element, or may be another element. The driving section 292is, for example, a hollow motor and includes a cylindrical fixed section292 a and a cylindrical rotating shaft 292 b. The rotating shaft 292 bis provided in a hollow portion of the fixed section 292 a to beconcentric with the fixed section 292 a. The driving section 292 iscontrolled by the driving control section 3 shown in FIG. 12.

In the measurement head 200, the driving section 292 is disposed suchthat the axes of the fixed section 292 a and the rotating shaft 292 bare located on the optical path of the measurement light MB. In thisstate, the flat member 291 is attached to the end portion of therotating shaft 292 b located further on the scanning section 270 sidethan the focusing section 260. The flat member 291 includessubstantially parallel two surfaces. One surface of the flat member 291is referred to as incident surface 291 a and the other surface isreferred to as emission surface 291 b. The flat member 291 is disposedin a state in which the incident surface 291 a and the emission surface291 b are inclined with respect to a surface orthogonal to a travelingdirection of the measurement light MB emitted from the focusing section260.

The measurement light MB traveling from the focusing section 260 to thescanning section 270 passes through the inside of the driving section292 and is made incident on the incident surface 291 a of the flatmember 291. In this case, since the incident surface 291 a is inclinedwith respect to the traveling direction of the measurement light MBemitted from the focusing section 260, the measurement light MB madeincident on the incident surface 291 a is transmitted through the flatmember 291 at an angle inclined with respect to an angle of incidence.Thereafter, the measurement light MB is emitted from the emissionsurface 291 b of the flat member 291 at an angle substantially equal tothe angle of incidence. In this state, as indicated by an alternate longand short dash line in FIG. 37, the rotating shaft 292 b rotatesaccording to the operation of the driving section 292. Consequently, themeasurement light MB is guided to the scanning section 270 while beingshifted to draw a circle on the surface orthogonal to the travelingdirection of the measurement light MB.

The scanning section 270 irradiates the measurement light MB shifted bythe shift mechanism 290 on the portion of the measurement object Scorresponding to the measurement point. At this point, the control board210 controls the driving sections 271 a and 272 a shown in FIG. 7 toirradiate the measurement light MB, which is not shifted, on the portionof the measurement object S corresponding to the measurement point.Consequently, the measurement light MB actually shifted by the shiftmechanism 290 is scanned on the annular partial region PA surroundingthe portion of the measurement object S corresponding to the measurementpoint. In this way, it is possible to irradiate light on the pluralityof portions P on the partial region PA.

With the configuration explained above, when a configuration includingthe scanning section 270 is existing, it is possible to easily reducethe unmeasurable region in the measurement object S by providing theshift mechanism 290 having a simple configuration in the configuration.

Note that the shift mechanism 290 only has to be provided between thelight guide section 240 and the scanning section 270 in the optical pathof the measurement light MB in the measurement head 200. For example,the shift mechanism 290 may be provided between the light guide section240 and the focusing section 260.

(b) In the embodiment explained above, the light receiving section 232 dmay temporarily accumulate, for each partial region PA shown in FIG. 8,electric charges obtained by receiving the measurement light reflectedfrom the plurality of portions P of the partial region PA. The lightreceiving section 232 d may give a light reception signal based on theelectric charges accumulated for each partial region PA to the controlboard 210. In this case, in the distance-information calculating section12 shown in FIG. 12, processing for integrating the plurality of lightreception signals corresponding to the plurality of portions P isunnecessary.

(c) FIG. 38 is a block diagram showing another configuration example ofthe control system 410 of the optical-scanning-height measuring device400. Concerning the control system 410 shown in FIG. 38, differencesfrom the control system 410 shown in FIG. 12 are explained. As shown inFIG. 38, in this example, the control system 410 further includes ageometric-element acquiring section 20 and a geometric-elementcalculating section 21.

In the setting mode, the geometric-element acquiring section 20 receivesdesignation of geometric elements concerning a position of a measurementpoint acquired by the position-information acquiring section 2. Thegeometric elements concerning the position of the measurement point arevarious elements that can be calculated on the basis of a coordinate ofa portion of the measurement object S corresponding to the measurementpoint. The geometric elements include, for example, flatness of adesired surface of the measurement object S and distances and angles ofa plurality of portions of the measurement object S. Allowable valuescorresponding to the designated geometric elements may be further inputto the allowable-value acquiring section 5.

The registering section 6 registers the geometric elements received bythe geometric-element acquiring section in association with themeasurement point. When the allowable values corresponding to thegeometric elements are input to the allowable-value acquiring section 5,the registering section 6 registers the allowable values received by theallowable-value acquiring section 5 in association with the geometricelements. The coordinate calculating section 13 further calculates acoordinate related to the geometric elements registered in theregistering section 6. The geometric-element calculating section 21calculates, on the basis of the coordinate related to the geometricelements calculated by the coordinate calculating section 13, values ofthe geometric elements registered in the registering section 6.

In the measurement mode, the correcting section 17 further sets, in themeasurement image data, the geometric elements corresponding to theregistration information registered by the registering section 6. Thecoordinate calculating section 13 further calculates a coordinaterelated to the geometric elements set by the correcting section 17. Thegeometric-element calculating section 21 calculates, on the basis of thecoordinate related to the geometric elements calculated by thecoordinate calculating section 13, geometric elements set by thecorrecting section 17.

With this configuration, since the measurement manager designates thegeometric elements in the setting mode, in the measurement mode, evenwhen the measurement operator is not skilled, it is possible touniformly acquire a calculation result of the geometric elements of thecorresponding portion of the measurement object S. Consequently, it ispossible to accurately and easily measure various geometric elementsincluding flatness and an assembling dimension of the measurement objectS.

When the allowable values corresponding to the geometric elements areregistered in the registering section 6, the inspecting section 18further inspects the measurement object S on the basis of the geometricelements calculated by the geometric-element calculating section 21 andthe allowable values registered in the registering section 6.Specifically, when the calculated geometric elements are within rangesof tolerances based on design values, the inspecting section 18determines that the measurement object S is a non-defective product. Onthe other hand, when the calculated geometric elements are outside theranges of the tolerances based on the design values, the inspectingsection 18 determines that the measurement object S is a defectiveproduct.

The report preparing section 19 prepares the report 420 shown in FIG. 13on the basis of the inspection result by the inspecting section 18 andthe reference image acquired by the measurement-image acquiring section16. In this case, inspection results of various geometric elements otherthan height are described in the report 420. In the example shown inFIG. 13, as the geometric elements, in addition to the height of theportion of the measurement object S, flatness, a difference in level,and an angle are described. Consequently, the measurement operator caninspect an assembling dimension of the measurement object S and caneasily report a result of the inspection to the measurement manager orthe other users using the report 420.

(d) FIG. 39 is a schematic diagram showing another configuration exampleof the optical section 230 of the optical-scanning-height measuringdevice 400. As shown in FIG. 39, the optical section 230 furtherincludes a guide light source 233 that emits, for example, light in avisible region. The light emitted by the guide light source 233 isreferred to as guide light. The light guide section 240 further includesa half mirror 247.

The half mirror 247 is disposed in a desired position on an optical pathof measurement light output from the port 245 d of the fiber coupler 245shown in FIG. 3. The half mirror 247 superimposes the guide lightemitted from the guide light source 233 and the measurement light outputfrom the port 245 d one on top of the other. Consequently, the guidelight is scanned by the scanning section 270 shown in FIG. 3 andirradiated on the measurement object S in a state in which the guidelight is superimposed on the measurement light.

With this configuration, the user can easily recognize an irradiationposition of light on the measurement object S from the scanning section270 by visually recognizing an irradiation position of the guide lighton the measurement object S. The imaging section 220 shown in FIG. 3 canclearly image the guide light on the measurement object S together withthe measurement light. Consequently, the image analyzing section 9 shownin FIG. 12 can more easily detect, as a plane coordinate indicating theirradiation position of the measurement light, a plane coordinateindicating the irradiation position of the guide light on the referenceimage or the measurement image. Note that, typically, the measurementlight is infrared light having low coherency. Typically, the imagingsection 220 cannot image the infrared light. Therefore, in this case,the imaging section 220 image the irradiation position of the guidelight as the irradiation position of the measurement light.

In this example, the guide light source 233 and the half mirror 247 areprovided such that the guide light overlaps the measurement light outputfrom the port 245 d of the fiber coupler 245. However, the presentinvention is not limited to this. The guide light source 233 and thehalf mirror 247 may be provided such that the guide light overlapsemission light output from the light emitting section 231 shown in FIG.3. In this case, the half mirror 247 is disposed in a desired positionon an optical path of the emission light between the light emittingsection 231 and the port 245 a of the fiber coupler 245.

In this example, the guide light and the measurement light aresuperimposed one on top of the other by the half mirror 247. However,the present invention is not limited to this. Typically, the measurementlight is infrared light having low coherency. The guide light includeslight in a visible region. Therefore, for example, the guide light andthe measurement light may be superimposed one on top of the other by awavelength selective mirror such as a dichroic mirror that shows highreflectance to light having a wavelength smaller than a cutoffwavelength and shows high transmittance to light having a wavelengthlarger than the cutoff wavelength. The guide light and the measurementlight may be superimposed one on top of the other by, for example, afiber coupler and an optical fiber. In this case, the fiber coupler hasa so-called 2×1 type configuration.

(e) The height calculating section 15 may calculate height of a portionof the measurement object S based on an origin in a peculiarthree-dimensional coordinate system defined in theoptical-scanning-height measuring device 400. In this case, the user canacquire the absolute value of the height of the portion of themeasurement object S in the peculiar three-dimensional coordinatesystem. The height calculating section 15 may be capable of selectivelyoperating in a relative value calculation mode for calculating therelative value of height based on a reference plane and an absolutevalue calculation mode for calculating the absolute value of height in apeculiar three-dimensional coordinate system. In the absolute valuecalculation mode, since the reference plane is unnecessary, thereference point may be not designated.

(f) In the setting mode, when height of the portion of the measurementobject S corresponding to the measurement point cannot be calculated,the height calculating section 15 may cause the display section 340 todisplay an error message such as “FAIL”. In this case, by visuallyrecognizing the display section 340, the measurement manager canrecognize that height of the portion of the measurement object Scorresponding to the measurement point cannot be calculated.Consequently, the measurement manager can change the disposition of themeasurement object S or the optical-scanning-height measuring device 400or change the position of a measurement point to be designated such thatheight of the portion of the measurement object S can be calculated.

(g) The optical-scanning-height measuring device 400 may be capable ofinserting a drawing and a comment into the reference image acquired inthe setting mode or the measurement image acquired in the measurementmode. Consequently, it is possible to record a measurement state of themeasurement object S more in detail. The drawing and the commentinserted into the reference image may be registered as the registrationinformation.

For example, a frame line indicating the search region set in thesetting mode may be drawn in the reference image. In this case, in themeasurement mode, the frame line is displayed on the measurement image.Consequently, in the measurement mode, it is easy for the measurementoperator to place the measurement object S on the optical surface plate111 such that the measurement object S fits inside the frame linedisplayed on the measurement image. As a result, it is possible toefficiently correct deviation of the measurement image data with respectto the reference image data.

(h) The reference-image acquiring section 1 may cause the displaysection 340 to display the acquired reference image in a bird's eye viewfashion by performing image processing of the reference image.Similarly, the measurement-image acquiring section 16 may cause thedisplay section 340 to display the acquired measurement image in abird's eye view fashion by performing image processing of themeasurement image.

(i) In the embodiments explained above, the reference-image acquiringsection 1 and the measurement-image acquiring section 16 acquire thecaptured image of the measurement object S by the imaging section 220respectively as the reference image and the measurement image. However,the present invention is not limited to this. The reference-imageacquiring section 1 and the measurement-image acquiring section 16 mayacquire a CAD (Computer Aided Design) image of the measurement object Sprepared in advance respectively as the reference image and themeasurement image.

Alternatively, when the measurement light is irradiated on a pluralityof portions of the measurement object S, the height calculating section15 is capable of calculating heights of the plurality of portions of themeasurement object S. Therefore, the reference-image acquiring section 1and the measurement-image acquiring section 16 may acquire a distanceimage of the measurement object S respectively as the reference imageand the measurement image on the basis of the heights of the pluralityof portions of the measurement object S.

When the CAD image or the distance image is used as the reference image,the measurement manager can accurately designate a desired referencepoint and a desired measurement point on the CAD image or the distanceimage while recognizing a three-dimensional shape of the measurementobject S. When the distance image is used as the reference image and themeasurement image, the distance image may be quickly generated byreducing resolution.

(j) In the embodiments explained above, the measurement operatordesignates the file of the registration image during the start of themeasurement mode. However, the invention is not limited to this. Forexample, an ID (identification) tag corresponding to the file of theregistration information may be stuck to the measurement object S. Inthis case, the ID tag is imaged by the imaging section 220 together withthe measurement object S during the start of the measurement mode,whereby the file of the registration information corresponding to thetag is automatically designated. With this configuration, themeasurement operator does not need to designate the file of theregistration information during the start of the measurement mode.Therefore, the processing in step S203 in FIG. 17 is omitted.

(k) In the embodiments explained above, the height of the measurementobject S is calculated by the spectral interference system. However, thepresent invention is not limited to this. The height of the measurementobject S may be calculated by another system such as a whiteinterference system, a confocal system, a triangulation system, or a TOF(time of flight) system.

(l) In the embodiments explained above, the light guide section 240includes the optical fibers 241 to 244 and the fiber coupler 245.However, the present invention is not limited to this. The light guidesection 240 may include a half mirror instead of the optical fibers 241to 244 and the fiber coupler 245.

(15) A Correspondence Relation Between the Constituent Elements of theClaims and the Sections of the Embodiments

An example of correspondence between the constituent elements of theclaims and the sections of the embodiments is explained below. However,the present invention is not limited to the example explained below.

In the embodiments explained above, the position-information acquiringsection 2 is an example of the position-information acquiring section,the light emitting section 231 is an example of the light emittingsection, the measurement object S is an example of the measurementobject, the partial region PA is an example of the partial region, theplurality of portions P is an example of the plurality of portions, thedeflecting sections 271 and 272, the driving control section 3, and theshift mechanism 290 are examples of the deflecting and irradiatingsection, the light receiving section 232 d is an example of the lightreceiving section, the detecting section 8 is an example of thedetecting section, the height calculating section 15 is an example ofthe height calculating section, and the optical-scanning-heightmeasuring device 400 is an example of the optical-scanning-heightmeasuring device.

The deflecting sections 271 and 272 are examples of the deflectingsection, the driving control section 3 is an example of the drivingcontrol section, the shift mechanism 290 is an example of the shiftsection, the setting section 110 is an example of the placement table,the measurement head 200 is an example of the head section, and theholding section 120 is an example of the holding section.

The imaging section 220 is an example of the imaging section, the linearguide 251 g is an example of the movement axis, the reflecting member254 c is an example of the reference body, the light guide section 240is an example of the light guide section, the reading sections 257 a and257 b are examples of the reference-position acquiring section, thespectral section 232 b is an example of the spectral section, and theregistering section 6 is an example of the registering section.

As the constituent elements of the claims, other various elements havingthe configurations or the functions described in the claims can also beused.

The present invention can be effectively used for variousoptical-scanning-height measuring devices.

What is claimed is:
 1. An optical-scanning-height measuring devicecomprising: a position-information receiver configured to receivedesignation of a measurement point; a light emitter configured to emitlight; a deflecting and irradiating section configured to deflect thelight emitted from the light emitter and irradiating the light on ameasurement object to sequentially irradiate the light on a plurality ofportions different from one another in a partial region on a surface ofthe measurement object including or surrounding a portion of themeasurement object corresponding to the measurement point received bythe position-information receiver; a light receiver configured toreceive light from the measurement object and output a light receptionsignal indicating a received light amount; a light detector configuredto detect a deflecting direction of the deflecting and irradiatingsection corresponding to the partial region or an irradiation positionof the measurement light corresponding to the partial region; and aheight calculator configured to calculate, on the basis of thedeflecting direction of the deflecting and irradiating section or theirradiation position of the measurement light detected by the lightdetector and the light reception signal output from the light receiveraccording to incidence of lights on the light receiver from theplurality of portions in the partial region, height of the portion ofthe measurement object corresponding to the designated measurementpoint.
 2. The optical-scanning-height measuring device according toclaim 1, wherein the deflecting and irradiating section includes: alight deflector configured to deflect the light emitted from the lightemitter and irradiate the light on the measurement object; and a drivingcontroller configured to control the light deflector to sequentiallyirradiate the light on the plurality of portions in the partial regioncorresponding to the measurement point received by theposition-information receiver.
 3. The optical-scanning-height measuringdevice according to claim 1, wherein the deflecting and irradiatingsection includes: a light deflector configured to deflect the lightemitted from the light emitter and irradiating the light on themeasurement object; a shift section provided between the light emitterand the light deflector and configured to shift a traveling direction ofthe light emitted from the light emitter to a direction orthogonal tothe traveling direction; and a driving controller configured to controlthe light deflector and the shift section to sequentially irradiate thelight on the plurality of portions in the partial region correspondingto the measurement point received by the position-information receiver.4. The optical-scanning-height measuring device according to claim 1,wherein the partial region is an annular region surrounding thedesignated measurement point, and the plurality of portions of thepartial region are arranged in a circumferential direction of theannular region.
 5. The optical-scanning-height measuring deviceaccording to claim 1, wherein, when the position-information receiversequentially receives designation of first and second measurementpoints, after the position-information receiver receives designation ofthe first measurement point and before the position-information receiverreceives designation of the second measurement point, the deflecting andirradiating section is capable of deflecting the light emitting from thelight emitter and irradiating the light on the measurement object tosequentially irradiate the light on a plurality of portions in a partialregion on the surface of the measurement object including or surroundinga portion of the measurement object corresponding to the designatedfirst measurement point.
 6. The optical-scanning-height measuring deviceaccording to claim 1, further comprising: a placement table on which themeasurement object is placed; a head body including the light emitter,the deflecting and irradiating section, and the light receiver; and aholding member configured to integrally hold the head body and theplacement table to irradiate, on a placement surface of the placementtable from above, the light emitted from the light emitter and deflectedby the deflecting and irradiating section.
 7. Theoptical-scanning-height measuring device according to claim 6, whereinthe holding member is capable of moving the head body in a directionorthogonal to the placement surface of the placement table.
 8. Theoptical-scanning-height measuring device according to claim 6, furthercomprising a camera provided in the head body and configured to imagethe measurement object placed on the placement table, wherein theposition-information receiver receives designation of a measurementpoint on an image of the measurement object acquired by the camera. 9.The optical-scanning-height measuring device according to claim 1,further comprising: a reference body disposed to be movable on amovement axis; a light guide configured to guide the light emitted bythe light emitter to the deflecting and irradiating section asmeasurement light and guide the light emitted by the light emitter tothe reference body as reference light, generate interference light ofthe measurement light from the measurement object reflected by thedeflecting and irradiating section and the reference light reflected bythe reference body, and guide the generated interference light to thelight receiver; a reference-position acquiring section configured toacquire a position of the reference body; and a spectral sectionconfigured to spectrally disperse the interference light generated bythe light guide, wherein the light emitter emits temporally low-coherentlight, the deflecting and irradiating section deflects the measurementlight guided by the light guide to irradiate the measurement light onthe plurality of portions in the partial region and reflects themeasurement light from the measurement object to the light guide, thelight receiver receives the interference light spectrally dispersed bythe spectral section and outputs a light reception signal indicating areceived light amount for each of wavelengths of the interference light,and the height calculator calculates height of the portion of themeasurement object on the basis of the position of the reference bodyacquired by the reference-position acquiring section and the receivedlight amount for each of the wavelengths of the interference light inthe light reception signal output from the light receiver.
 10. Theoptical-scanning-height measuring device according to claim 1, whereinthe optical-scanning-height measuring device is configured toselectively operate in a setting mode and a measurement mode and furthercomprises a registering section, the position-information receiverreceives, in the setting mode, the measurement point on an image of afirst measurement object, the registering section registers, in thesetting mode, the measurement point received by the position-informationreceiver, the deflecting and irradiating section deflects, in themeasurement mode, the light emitted from the light emitter andirradiates the light on the measurement object to sequentially irradiatethe light on a plurality of portions different from one another in apartial region on a surface of a second measurement object including orsurrounding a portion of the second measurement object corresponding tothe measurement point registered by the registering section, the lightdetector detects, in the measurement mode, a deflecting direction of thedeflecting and irradiating section corresponding to the partial regionor an irradiation position of the measurement light corresponding to thepartial region, and the height calculator calculates, in the measurementmode, height of the portion of the second measurement objectcorresponding to the measurement point.